From 0886ada39c4651fcd0a8bec5bce4358972791c45 Mon Sep 17 00:00:00 2001
From: Ronald Barendse <ronald@panoramastudios.nl>
Date: Fri, 19 Jun 2020 11:41:16 +0200
Subject: [PATCH] Properly HTML encode text in helper methods (#6545)

---
 .../PublishedContent/IndexedArrayItem.cs      | 293 +++++++++++++++++-
 src/Umbraco.Web/HtmlHelperRenderExtensions.cs |  77 +++--
 src/Umbraco.Web/HtmlStringUtilities.cs        |  14 +-
 src/Umbraco.Web/Mvc/HtmlTagWrapperTextNode.cs |   2 +-
 src/Umbraco.Web/PublishedContentExtensions.cs | 149 ++++++++-
 5 files changed, 489 insertions(+), 46 deletions(-)

diff --git a/src/Umbraco.Core/Models/PublishedContent/IndexedArrayItem.cs b/src/Umbraco.Core/Models/PublishedContent/IndexedArrayItem.cs
index 5dc42cc542..f7d13fcf90 100644
--- a/src/Umbraco.Core/Models/PublishedContent/IndexedArrayItem.cs
+++ b/src/Umbraco.Core/Models/PublishedContent/IndexedArrayItem.cs
@@ -2,168 +2,441 @@
 
 namespace Umbraco.Core.Models.PublishedContent
 {
+    /// <summary>
+    /// Represents an item in an array that stores its own index and the total count.
+    /// </summary>
+    /// <typeparam name="TContent">The type of the content.</typeparam>
     public class IndexedArrayItem<TContent>
     {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="IndexedArrayItem{TContent}" /> class.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="index">The index.</param>
         public IndexedArrayItem(TContent content, int index)
         {
             Content = content;
             Index = index;
         }
 
+        /// <summary>
+        /// Gets the content.
+        /// </summary>
+        /// <value>
+        /// The content.
+        /// </value>
         public TContent Content { get; }
 
+        /// <summary>
+        /// Gets the index.
+        /// </summary>
+        /// <value>
+        /// The index.
+        /// </value>
         public int Index { get; }
 
+        /// <summary>
+        /// Gets the total count.
+        /// </summary>
+        /// <value>
+        /// The total count.
+        /// </value>
         public int TotalCount { get; internal set; }
 
+        /// <summary>
+        /// Determines whether this item is the first.
+        /// </summary>
+        /// <returns>
+        ///   <c>true</c> if this item is the first; otherwise, <c>false</c>.
+        /// </returns>
         public bool IsFirst()
         {
             return Index == 0;
         }
 
+        /// <summary>
+        /// If this item is the first, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsFirst(string valueIfTrue)
         {
             return IsFirst(valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is the first, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsFirst(string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsFirst() ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsFirst() ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is not the first.
+        /// </summary>
+        /// <returns>
+        ///   <c>true</c> if this item is not the first; otherwise, <c>false</c>.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public bool IsNotFirst()
         {
             return IsFirst() == false;
         }
 
+        /// <summary>
+        /// If this item is not the first, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotFirst(string valueIfTrue)
         {
             return IsNotFirst(valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is not the first, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotFirst(string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsNotFirst() ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsNotFirst() ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is at the specified <paramref name="index" />.
+        /// </summary>
+        /// <param name="index">The index.</param>
+        /// <returns>
+        ///   <c>true</c> if this item is at the specified <paramref name="index" />; otherwise, <c>false</c>.
+        /// </returns>
         public bool IsIndex(int index)
         {
             return Index == index;
         }
 
+        /// <summary>
+        /// If this item is at the specified <paramref name="index" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="index">The index.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsIndex(int index, string valueIfTrue)
         {
             return IsIndex(index, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is at the specified <paramref name="index" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="index">The index.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsIndex(int index, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsIndex(index) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsIndex(index) ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is at an index that can be divided by the specified <paramref name="modulus" />.
+        /// </summary>
+        /// <param name="modulus">The modulus.</param>
+        /// <returns>
+        ///   <c>true</c> if this item is at an index that can be divided by the specified <paramref name="modulus" />; otherwise, <c>false</c>.
+        /// </returns>
         public bool IsModZero(int modulus)
         {
             return Index % modulus == 0;
         }
 
+        /// <summary>
+        /// If this item is at an index that can be divided by the specified <paramref name="modulus" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="modulus">The modulus.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsModZero(int modulus, string valueIfTrue)
         {
             return IsModZero(modulus, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is at an index that can be divided by the specified <paramref name="modulus" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="modulus">The modulus.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsModZero(int modulus, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsModZero(modulus) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsModZero(modulus) ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is not at an index that can be divided by the specified <paramref name="modulus" />.
+        /// </summary>
+        /// <param name="modulus">The modulus.</param>
+        /// <returns>
+        ///   <c>true</c> if this item is not at an index that can be divided by the specified <paramref name="modulus" />; otherwise, <c>false</c>.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public bool IsNotModZero(int modulus)
         {
             return IsModZero(modulus) == false;
         }
 
+        /// <summary>
+        /// If this item is not at an index that can be divided by the specified <paramref name="modulus" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="modulus">The modulus.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotModZero(int modulus, string valueIfTrue)
         {
             return IsNotModZero(modulus, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is not at an index that can be divided by the specified <paramref name="modulus" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="modulus">The modulus.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotModZero(int modulus, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsNotModZero(modulus) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsNotModZero(modulus) ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is not at the specified <paramref name="index" />.
+        /// </summary>
+        /// <param name="index">The index.</param>
+        /// <returns>
+        ///   <c>true</c> if this item is not at the specified <paramref name="index" />; otherwise, <c>false</c>.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public bool IsNotIndex(int index)
         {
             return IsIndex(index) == false;
         }
 
+        /// <summary>
+        /// If this item is not at the specified <paramref name="index" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="index">The index.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotIndex(int index, string valueIfTrue)
         {
             return IsNotIndex(index, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is at the specified <paramref name="index" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="index">The index.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotIndex(int index, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsNotIndex(index) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsNotIndex(index) ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is the last.
+        /// </summary>
+        /// <returns>
+        ///   <c>true</c> if this item is the last; otherwise, <c>false</c>.
+        /// </returns>
         public bool IsLast()
         {
             return Index == TotalCount - 1;
         }
 
+        /// <summary>
+        /// If this item is the last, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsLast(string valueIfTrue)
         {
             return IsLast(valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is the last, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsLast(string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsLast() ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsLast() ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is not the last.
+        /// </summary>
+        /// <returns>
+        ///   <c>true</c> if this item is not the last; otherwise, <c>false</c>.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public bool IsNotLast()
         {
             return IsLast() == false;
         }
 
+        /// <summary>
+        /// If this item is not the last, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotLast(string valueIfTrue)
         {
             return IsNotLast(valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is not the last, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsNotLast(string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsNotLast() ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsNotLast() ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is at an even index.
+        /// </summary>
+        /// <returns>
+        ///   <c>true</c> if this item is at an even index; otherwise, <c>false</c>.
+        /// </returns>
         public bool IsEven()
         {
             return Index % 2 == 0;
         }
 
+        /// <summary>
+        /// If this item is at an even index, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsEven(string valueIfTrue)
         {
             return IsEven(valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is at an even index, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsEven(string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsEven() ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsEven() ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// Determines whether this item is at an odd index.
+        /// </summary>
+        /// <returns>
+        ///   <c>true</c> if this item is at an odd index; otherwise, <c>false</c>.
+        /// </returns>
         public bool IsOdd()
         {
             return Index % 2 == 1;
         }
 
+        /// <summary>
+        /// If this item is at an odd index, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsOdd(string valueIfTrue)
         {
             return IsOdd(valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If this item is at an odd index, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public HtmlString IsOdd(string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(IsOdd() ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(IsOdd() ? valueIfTrue : valueIfFalse));
         }
     }
 }
diff --git a/src/Umbraco.Web/HtmlHelperRenderExtensions.cs b/src/Umbraco.Web/HtmlHelperRenderExtensions.cs
index ebe5e08f89..4b1de86bcf 100644
--- a/src/Umbraco.Web/HtmlHelperRenderExtensions.cs
+++ b/src/Umbraco.Web/HtmlHelperRenderExtensions.cs
@@ -253,12 +253,12 @@ namespace Umbraco.Web
         }
 
         /// <summary>
-        /// Helper method to create a new form to execute in the Umbraco request pipeline against a locally declared controller
+        /// Helper method to create a new form to execute in the Umbraco request pipeline against a locally declared controller.
         /// </summary>
-        /// <param name="html"></param>
-        /// <param name="action"></param>
-        /// <param name="controllerName"></param>
-        /// <param name="method"></param>
+        /// <param name="html">The HTML helper.</param>
+        /// <param name="action">Name of the action.</param>
+        /// <param name="controllerName">Name of the controller.</param>
+        /// <param name="method">The method.</param>
         /// <returns></returns>
         public static MvcForm BeginUmbracoForm(this HtmlHelper html, string action, string controllerName, FormMethod method)
         {
@@ -315,9 +315,9 @@ namespace Umbraco.Web
         /// <param name="method"></param>
         /// <returns></returns>
         public static MvcForm BeginUmbracoForm(this HtmlHelper html, string action, string controllerName,
-                                               object additionalRouteVals,
-                                               object htmlAttributes,
-                                               FormMethod method)
+            object additionalRouteVals,
+            object htmlAttributes,
+            FormMethod method)
         {
             return html.BeginUmbracoForm(action, controllerName, additionalRouteVals, HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes), method);
         }
@@ -332,8 +332,8 @@ namespace Umbraco.Web
         /// <param name="htmlAttributes"></param>
         /// <returns></returns>
         public static MvcForm BeginUmbracoForm(this HtmlHelper html, string action, string controllerName,
-                                               object additionalRouteVals,
-                                               object htmlAttributes)
+            object additionalRouteVals,
+            object htmlAttributes)
         {
             return html.BeginUmbracoForm(action, controllerName, additionalRouteVals, HtmlHelper.AnonymousObjectToHtmlAttributes(htmlAttributes));
         }
@@ -349,9 +349,9 @@ namespace Umbraco.Web
         /// <param name="method"></param>
         /// <returns></returns>
         public static MvcForm BeginUmbracoForm(this HtmlHelper html, string action, string controllerName,
-                                               object additionalRouteVals,
-                                               IDictionary<string, object> htmlAttributes,
-                                               FormMethod method)
+            object additionalRouteVals,
+            IDictionary<string, object> htmlAttributes,
+            FormMethod method)
         {
             if (action == null) throw new ArgumentNullException(nameof(action));
             if (string.IsNullOrWhiteSpace(action)) throw new ArgumentException("Value can't be empty or consist only of white-space characters.", nameof(action));
@@ -371,8 +371,8 @@ namespace Umbraco.Web
         /// <param name="htmlAttributes"></param>
         /// <returns></returns>
         public static MvcForm BeginUmbracoForm(this HtmlHelper html, string action, string controllerName,
-                                               object additionalRouteVals,
-                                               IDictionary<string, object> htmlAttributes)
+            object additionalRouteVals,
+            IDictionary<string, object> htmlAttributes)
         {
             if (action == null) throw new ArgumentNullException(nameof(action));
             if (string.IsNullOrWhiteSpace(action)) throw new ArgumentException("Value can't be empty or consist only of white-space characters.", nameof(action));
@@ -840,19 +840,32 @@ namespace Umbraco.Web
         #region If
 
         /// <summary>
-        /// If the test is true, the string valueIfTrue will be returned, otherwise the valueIfFalse will be returned.
+        /// If <paramref name="test" /> is <c>true</c>, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
         /// </summary>
-        public static IHtmlString If(this HtmlHelper html, bool test, string valueIfTrue, string valueIfFalse)
+        /// <param name="html">The HTML helper.</param>
+        /// <param name="test">If set to <c>true</c> returns <paramref name="valueIfTrue" />; otherwise, <see cref="string.Empty" />.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        public static IHtmlString If(this HtmlHelper html, bool test, string valueIfTrue)
         {
-            return test ? new HtmlString(valueIfTrue) : new HtmlString(valueIfFalse);
+            return If(html, test, valueIfTrue, string.Empty);
         }
 
         /// <summary>
-        /// If the test is true, the string valueIfTrue will be returned, otherwise the valueIfFalse will be returned.
+        /// If <paramref name="test" /> is <c>true</c>, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
         /// </summary>
-        public static IHtmlString If(this HtmlHelper html, bool test, string valueIfTrue)
+        /// <param name="html">The HTML helper.</param>
+        /// <param name="test">If set to <c>true</c> returns <paramref name="valueIfTrue" />; otherwise, <paramref name="valueIfFalse" />.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        public static IHtmlString If(this HtmlHelper html, bool test, string valueIfTrue, string valueIfFalse)
         {
-            return test ? new HtmlString(valueIfTrue) : new HtmlString(string.Empty);
+            return new HtmlString(HttpUtility.HtmlEncode(test ? valueIfTrue : valueIfFalse));
         }
 
         #endregion
@@ -862,16 +875,32 @@ namespace Umbraco.Web
         private static readonly HtmlStringUtilities StringUtilities = new HtmlStringUtilities();
 
         /// <summary>
-        /// Replaces text line breaks with HTML line breaks
+        /// Replaces text line breaks with HTML line breaks.
         /// </summary>
-        /// <param name="helper"></param>
+        /// <param name="helper">The HTML helper.</param>
         /// <param name="text">The text.</param>
-        /// <returns>The text with text line breaks replaced with HTML line breaks (<br/>)</returns>
+        /// <returns>
+        /// The text with text line breaks replaced with HTML line breaks (<c>&lt;br /&gt;</c>).
+        /// </returns>
+        [Obsolete("This method doesn't HTML encode the text. Use ReplaceLineBreaks instead.")]
         public static IHtmlString ReplaceLineBreaksForHtml(this HtmlHelper helper, string text)
         {
             return StringUtilities.ReplaceLineBreaksForHtml(text);
         }
 
+        /// <summary>
+        /// HTML encodes the text and replaces text line breaks with HTML line breaks.
+        /// </summary>
+        /// <param name="helper">The HTML helper.</param>
+        /// <param name="text">The text.</param>
+        /// <returns>
+        /// The HTML encoded text with text line breaks replaced with HTML line breaks (<c>&lt;br /&gt;</c>).
+        /// </returns>
+        public static IHtmlString ReplaceLineBreaks(this HtmlHelper helper, string text)
+        {
+            return StringUtilities.ReplaceLineBreaks(text);
+        }
+
         /// <summary>
         /// Generates a hash based on the text string passed in.  This method will detect the
         /// security requirements (is FIPS enabled) and return an appropriate hash.
diff --git a/src/Umbraco.Web/HtmlStringUtilities.cs b/src/Umbraco.Web/HtmlStringUtilities.cs
index a8cbb70019..7df3e69bcb 100644
--- a/src/Umbraco.Web/HtmlStringUtilities.cs
+++ b/src/Umbraco.Web/HtmlStringUtilities.cs
@@ -16,21 +16,25 @@ namespace Umbraco.Web
     public sealed class HtmlStringUtilities
     {
         /// <summary>
-        /// Replaces text line breaks with HTML line breaks
+        /// Replaces text line breaks with HTML line breaks.
         /// </summary>
         /// <param name="text">The text.</param>
-        /// <returns>The text with text line breaks replaced with HTML line breaks (<c>&lt;br /&gt;</c>).
+        /// <returns>
+        /// The text with text line breaks replaced with HTML line breaks (<c>&lt;br /&gt;</c>).
+        /// </returns>
         [Obsolete("This method doesn't HTML encode the text. Use ReplaceLineBreaks instead.")]
         public HtmlString ReplaceLineBreaksForHtml(string text)
         {
-            return new HtmlString(text.Replace("\r\n", @"<br />").Replace("\n", @"<br />").Replace("\r", @"<br />"));            
+            return new HtmlString(text.Replace("\r\n", @"<br />").Replace("\n", @"<br />").Replace("\r", @"<br />"));
         }
-        
+
         /// <summary>
         /// HTML encodes the text and replaces text line breaks with HTML line breaks.
         /// </summary>
         /// <param name="text">The text.</param>
-        /// <returns>The HTML encoded text with text line breaks replaced with HTML line breaks (<c>&lt;br /&gt;</c>).</returns>
+        /// <returns>
+        /// The HTML encoded text with text line breaks replaced with HTML line breaks (<c>&lt;br /&gt;</c>).
+        /// </returns>
         public IHtmlString ReplaceLineBreaks(string text)
         {
             var value = HttpUtility.HtmlEncode(text)?
diff --git a/src/Umbraco.Web/Mvc/HtmlTagWrapperTextNode.cs b/src/Umbraco.Web/Mvc/HtmlTagWrapperTextNode.cs
index 43bfedde86..1085c2a279 100644
--- a/src/Umbraco.Web/Mvc/HtmlTagWrapperTextNode.cs
+++ b/src/Umbraco.Web/Mvc/HtmlTagWrapperTextNode.cs
@@ -12,7 +12,7 @@ namespace Umbraco.Web.Mvc
 
         public void WriteToHtmlTextWriter(System.Web.UI.HtmlTextWriter html)
         {
-            html.Write(Content);
+            html.WriteEncodedText(Content);
         }
     }
 }
diff --git a/src/Umbraco.Web/PublishedContentExtensions.cs b/src/Umbraco.Web/PublishedContentExtensions.cs
index 750ffa4be6..73148b667a 100644
--- a/src/Umbraco.Web/PublishedContentExtensions.cs
+++ b/src/Umbraco.Web/PublishedContentExtensions.cs
@@ -287,29 +287,82 @@ namespace Umbraco.Web
             return content.Id == other.Id;
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is equal to <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsEqual(this IPublishedContent content, IPublishedContent other, string valueIfTrue)
         {
             return content.IsEqual(other, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is equal to <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsEqual(this IPublishedContent content, IPublishedContent other, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(content.IsEqual(other) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(content.IsEqual(other) ? valueIfTrue : valueIfFalse));
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is not equal to <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static bool IsNotEqual(this IPublishedContent content, IPublishedContent other)
         {
             return content.IsEqual(other) == false;
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is not equal to <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsNotEqual(this IPublishedContent content, IPublishedContent other, string valueIfTrue)
         {
             return content.IsNotEqual(other, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is not equal to <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsNotEqual(this IPublishedContent content, IPublishedContent other, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(content.IsNotEqual(other) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(content.IsNotEqual(other) ? valueIfTrue : valueIfFalse));
         }
 
         #endregion
@@ -321,14 +374,35 @@ namespace Umbraco.Web
             return other.Level < content.Level && content.Path.InvariantStartsWith(other.Path.EnsureEndsWith(','));
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is a decendant of <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsDescendant(this IPublishedContent content, IPublishedContent other, string valueIfTrue)
         {
             return content.IsDescendant(other, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is a decendant of <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsDescendant(this IPublishedContent content, IPublishedContent other, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(content.IsDescendant(other) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(content.IsDescendant(other) ? valueIfTrue : valueIfFalse));
         }
 
         public static bool IsDescendantOrSelf(this IPublishedContent content, IPublishedContent other)
@@ -336,14 +410,35 @@ namespace Umbraco.Web
             return content.Path.InvariantEquals(other.Path) || content.IsDescendant(other);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is a decendant of <paramref name="other" /> or are the same, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsDescendantOrSelf(this IPublishedContent content, IPublishedContent other, string valueIfTrue)
         {
             return content.IsDescendantOrSelf(other, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is a decendant of <paramref name="other" /> or are the same, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsDescendantOrSelf(this IPublishedContent content, IPublishedContent other, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(content.IsDescendantOrSelf(other) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(content.IsDescendantOrSelf(other) ? valueIfTrue : valueIfFalse));
         }
 
         public static bool IsAncestor(this IPublishedContent content, IPublishedContent other)
@@ -351,14 +446,35 @@ namespace Umbraco.Web
             return content.Level < other.Level && other.Path.InvariantStartsWith(content.Path.EnsureEndsWith(','));
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is an ancestor of <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsAncestor(this IPublishedContent content, IPublishedContent other, string valueIfTrue)
         {
             return content.IsAncestor(other, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is an ancestor of <paramref name="other" />, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsAncestor(this IPublishedContent content, IPublishedContent other, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(content.IsAncestor(other) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(content.IsAncestor(other) ? valueIfTrue : valueIfFalse));
         }
 
         public static bool IsAncestorOrSelf(this IPublishedContent content, IPublishedContent other)
@@ -366,14 +482,35 @@ namespace Umbraco.Web
             return other.Path.InvariantEquals(content.Path) || content.IsAncestor(other);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is an ancestor of <paramref name="other" /> or are the same, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <see cref="string.Empty" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsAncestorOrSelf(this IPublishedContent content, IPublishedContent other, string valueIfTrue)
         {
             return content.IsAncestorOrSelf(other, valueIfTrue, string.Empty);
         }
 
+        /// <summary>
+        /// If the specified <paramref name="content" /> is an ancestor of <paramref name="other" /> or are the same, the HTML encoded <paramref name="valueIfTrue" /> will be returned; otherwise, <paramref name="valueIfFalse" />.
+        /// </summary>
+        /// <param name="content">The content.</param>
+        /// <param name="other">The other content.</param>
+        /// <param name="valueIfTrue">The value if <c>true</c>.</param>
+        /// <param name="valueIfFalse">The value if <c>false</c>.</param>
+        /// <returns>
+        /// The HTML encoded value.
+        /// </returns>
+        // TODO: This method should be removed or moved to an extension method on HtmlHelper.
         public static HtmlString IsAncestorOrSelf(this IPublishedContent content, IPublishedContent other, string valueIfTrue, string valueIfFalse)
         {
-            return new HtmlString(content.IsAncestorOrSelf(other) ? valueIfTrue : valueIfFalse);
+            return new HtmlString(HttpUtility.HtmlEncode(content.IsAncestorOrSelf(other) ? valueIfTrue : valueIfFalse));
         }
 
         #endregion