Remove closure from JsonWebTokenHandler.ValidateSignature (#2169)

The Any call on an exceptional path is closing over the jwtToken parameter, which means a display class gets allocated at the beginning of the method, whether that code path is taken or not.
AzureAD · Jul 26, 2023 · 4d1e7b0 · 4d1e7b0
1 parent 8e6e190
commit 4d1e7b0
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/Microsoft.IdentityModel.JsonWebTokens/JsonWebTokenHandler.cs b/src/Microsoft.IdentityModel.JsonWebTokens/JsonWebTokenHandler.cs
@@ -1760,7 +1760,8 @@ private static JsonWebToken ValidateSignature(JsonWebToken jwtToken, TokenValida
             {
                 if (kidMatched)
                 {
-                    var isKidInTVP = keysInTokenValidationParameters.Any(x => x.KeyId.Equals(jwtToken.Kid));
+                    JsonWebToken localJwtToken = jwtToken; // avoid closure on non-exceptional path
+                    var isKidInTVP = keysInTokenValidationParameters.Any(x => x.KeyId.Equals(localJwtToken.Kid));
                     var keyLocation = isKidInTVP ? "TokenValidationParameters" : "Configuration";
                     throw LogHelper.LogExceptionMessage(new SecurityTokenInvalidSignatureException(LogHelper.FormatInvariant(TokenLogMessages.IDX10511,
                         keysAttempted,