diff --git a/test/fixtures/wpt/README.md b/test/fixtures/wpt/README.md
index 94d0cf01d87083..cd16d09991969c 100644
--- a/test/fixtures/wpt/README.md
+++ b/test/fixtures/wpt/README.md
@@ -34,7 +34,7 @@ Last update:
 - wasm/jsapi: https://github.com/web-platform-tests/wpt/tree/288c467d35/wasm/jsapi
 - wasm/webapi: https://github.com/web-platform-tests/wpt/tree/fd1b23eeaa/wasm/webapi
 - web-locks: https://github.com/web-platform-tests/wpt/tree/10a122a6bc/web-locks
-- WebCryptoAPI: https://github.com/web-platform-tests/wpt/tree/0c413fb56b/WebCryptoAPI
+- WebCryptoAPI: https://github.com/web-platform-tests/wpt/tree/03a1476844/WebCryptoAPI
 - webidl: https://github.com/web-platform-tests/wpt/tree/63ca529a02/webidl
 - webidl/ecmascript-binding/es-exceptions: https://github.com/web-platform-tests/wpt/tree/2f96fa1996/webidl/ecmascript-binding/es-exceptions
 - webmessaging/broadcastchannel: https://github.com/web-platform-tests/wpt/tree/6495c91853/webmessaging/broadcastchannel
diff --git a/test/fixtures/wpt/WebCryptoAPI/import_export/symmetric_importKey.js b/test/fixtures/wpt/WebCryptoAPI/import_export/symmetric_importKey.js
index 8633af5279caa1..795d90ffbff4fd 100644
--- a/test/fixtures/wpt/WebCryptoAPI/import_export/symmetric_importKey.js
+++ b/test/fixtures/wpt/WebCryptoAPI/import_export/symmetric_importKey.js
@@ -59,6 +59,20 @@ function runTests(algorithmName) {
                         testFormat(format, algorithm, data, keyData.length * 8, usages, extractable);
                     });
                     testEmptyUsages(format, algorithm, data, keyData.length * 8, extractable);
+
+                    // Verify the key data is copied only after the algorithm is
+                    // normalized (per spec, "get a copy of the bytes held by the
+                    // keyData parameter" follows "normalize an algorithm"). A
+                    // getter on the algorithm name mutates the key data during
+                    // normalization; the imported key must reflect the restored
+                    // bytes. Checked for BufferSource formats (jwk key data is
+                    // not a BufferSource) when the key is extractable, so the
+                    // imported bytes can be read back and compared.
+                    if (extractable && format !== "jwk") {
+                        allValidUsages(vector.legalUsages).forEach(function(usages) {
+                            testKeyDataAlteredDuringCall(format, algorithm, keyData, keyData.length * 8, usages);
+                        });
+                    }
                 });
             });
 
@@ -111,6 +125,35 @@ function runTests(algorithmName) {
         }, "Empty Usages: " + keySize.toString() + " bits " + parameterString(format, keyData, algorithm, extractable, usages));
     }
 
+    // Test that importKey copies the key data only after the algorithm has been
+    // normalized. The spec normalizes the algorithm (which can run author
+    // getters on the algorithm dictionary) before getting a copy of the bytes
+    // held by the keyData parameter. Here a getter on the algorithm's name
+    // mutates the key data during normalization and then restores it, so a
+    // spec-compliant implementation imports the restored (original) bytes.
+    function testKeyDataAlteredDuringCall(format, algorithm, keyData, keySize, usages) {
+        promise_test(function(test) {
+            var alteredKeyData = copyBuffer(keyData);
+            alteredKeyData[0] = 255 - alteredKeyData[0];
+            var algorithmWithGetter = {
+                ...algorithm,
+                get name() {
+                    alteredKeyData[0] = keyData[0];
+                    return algorithm.name;
+                }
+            };
+            return subtle.importKey(format, alteredKeyData, algorithmWithGetter, true, usages).
+            then(function(key) {
+                return subtle.exportKey(format, key);
+            }).
+            then(function(result) {
+                assert_true(equalBuffers(keyData, result), "Imported key reflects the key data as it was after normalization");
+            }, function(err) {
+                assert_unreached("Threw an unexpected error: " + err.toString());
+            });
+        }, "Key data altered during call: " + keySize.toString() + " bits " + parameterString(format, keyData, algorithm, true, usages));
+    }
+
 
 
     // Helper methods follow:
diff --git a/test/fixtures/wpt/versions.json b/test/fixtures/wpt/versions.json
index 4921aa48d0fd82..d1929a839269e5 100644
--- a/test/fixtures/wpt/versions.json
+++ b/test/fixtures/wpt/versions.json
@@ -96,7 +96,7 @@
     "path": "web-locks"
   },
   "WebCryptoAPI": {
-    "commit": "0c413fb56b9da8bf27502c866a3d60f93981804d",
+    "commit": "03a14768441c1ce2a31678d0dc080e81dc449d0a",
     "path": "WebCryptoAPI"
   },
   "webidl": {