diff --git a/src/Runner.Plugins/Repository/v1.0/RepositoryPlugin.cs b/src/Runner.Plugins/Repository/v1.0/RepositoryPlugin.cs
index fd78da8499a..f1348532183 100644
--- a/src/Runner.Plugins/Repository/v1.0/RepositoryPlugin.cs
+++ b/src/Runner.Plugins/Repository/v1.0/RepositoryPlugin.cs
@@ -12,8 +12,6 @@ namespace GitHub.Runner.Plugins.Repository.v1_0
 {
     public class CheckoutTask : IRunnerActionPlugin
     {
-        private readonly Regex _validSha1 = new(@"\b[0-9a-f]{40}\b", RegexOptions.IgnoreCase | RegexOptions.CultureInvariant | RegexOptions.Compiled, TimeSpan.FromSeconds(2));
-
         public async Task RunAsync(RunnerActionPluginExecutionContext executionContext, CancellationToken token)
         {
             string runnerWorkspace = executionContext.GetRunnerContext("workspace");
diff --git a/src/Sdk/DTPipelines/Pipelines/Expressions/WellKnownRegularExpressions.cs b/src/Sdk/DTPipelines/Pipelines/Expressions/WellKnownRegularExpressions.cs
index 72899fb4253..d4d3c75a64c 100644
--- a/src/Sdk/DTPipelines/Pipelines/Expressions/WellKnownRegularExpressions.cs
+++ b/src/Sdk/DTPipelines/Pipelines/Expressions/WellKnownRegularExpressions.cs
@@ -8,6 +8,7 @@ public static class WellKnownRegularExpressions
         public const String Email = nameof(Email);
         public const String IPv4Address = nameof(IPv4Address);
         public const String SHA1 = nameof(SHA1);
+        public const String CommitHash = nameof(CommitHash);
         public const String Url = nameof(Url);
 
         /// <summary>
@@ -24,7 +25,8 @@ public static Lazy<Regex> GetRegex(String regexType)
                 case IPv4Address:
                     return s_validIPv4Address;
                 case SHA1:
-                    return s_validSha1;
+                case CommitHash:
+                    return s_validCommitHash;
                 case Url:
                     return s_validUrl;
                 default:
@@ -46,9 +48,9 @@ public static Lazy<Regex> GetRegex(String regexType)
             )
         );
 
-        // 40 hex characters
-        private static readonly Lazy<Regex> s_validSha1 = new Lazy<Regex>(() => new Regex(
-            @"\b[0-9a-f]{40}\b",
+        // 40 or 64 hex characters (SHA-1 or SHA-256 commit hash)
+        private static readonly Lazy<Regex> s_validCommitHash = new Lazy<Regex>(() => new Regex(
+            @"\b(?:[0-9a-f]{40}|[0-9a-f]{64})\b",
             RegexOptions.IgnoreCase | RegexOptions.CultureInvariant | RegexOptions.Compiled, RegexUtility.GetRegexTimeOut()
             )
         );
diff --git a/src/Test/L0/Sdk/WellKnownRegularExpressionsL0.cs b/src/Test/L0/Sdk/WellKnownRegularExpressionsL0.cs
new file mode 100644
index 00000000000..ffd3846bdb2
--- /dev/null
+++ b/src/Test/L0/Sdk/WellKnownRegularExpressionsL0.cs
@@ -0,0 +1,100 @@
+using GitHub.DistributedTask.Pipelines.Expressions;
+using Xunit;
+
+namespace GitHub.Runner.Common.Tests.Sdk
+{
+    public sealed class WellKnownRegularExpressionsL0
+    {
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void SHA1_Key_Returns_CommitHash_Regex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.SHA1);
+
+            Assert.NotNull(regex);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void CommitHash_Key_Returns_CommitHash_Regex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.NotNull(regex);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void SHA1_And_CommitHash_Return_Same_Regex()
+        {
+            var sha1Regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.SHA1);
+            var commitHashRegex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.Same(sha1Regex, commitHashRegex);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Matches_40_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.Matches(regex.Value, new string((char)97, 40));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Matches_64_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.Matches(regex.Value, new string((char)97, 64));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Does_Not_Match_63_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.DoesNotMatch(regex.Value, new string((char)97, 63));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Does_Not_Match_65_Char_Hex()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+
+            Assert.DoesNotMatch(regex.Value, new string((char)97, 65));
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Matches_Mixed_Case_64_Char()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex(WellKnownRegularExpressions.CommitHash);
+            var value = new string((char)65, 32) + new string((char)98, 32);
+
+            Assert.Matches(regex.Value, value);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Sdk")]
+        public void Unknown_Key_Returns_Null()
+        {
+            var regex = WellKnownRegularExpressions.GetRegex("UnknownType");
+
+            Assert.Null(regex);
+        }
+    }
+}