diff --git a/CHANGELOG.md b/CHANGELOG.md
index 297c6a7f1e4b45..3c265902e7e281 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,7 +32,8 @@ release.
 </tr>
 <tr>
     <td valign="top">
-<b><a href="doc/changelogs/CHANGELOG_V16.md#16.9.0">16.9.0</a></b><br/>
+<b><a href="doc/changelogs/CHANGELOG_V16.md#16.9.1">16.9.1</a></b><br/>
+<a href="doc/changelogs/CHANGELOG_V16.md#16.9.0">16.9.0</a><br/>
 <a href="doc/changelogs/CHANGELOG_V16.md#16.8.0">16.8.0</a><br/>
 <a href="doc/changelogs/CHANGELOG_V16.md#16.7.0">16.7.0</a><br/>
 <a href="doc/changelogs/CHANGELOG_V16.md#16.6.2">16.6.2</a><br/>
diff --git a/common.gypi b/common.gypi
index 0f8999f4079994..013f24b107408f 100644
--- a/common.gypi
+++ b/common.gypi
@@ -36,7 +36,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.11',
+    'v8_embedder_string': '-node.12',
 
     ##### V8 defaults for Node.js #####
 
diff --git a/deps/v8/src/objects/lookup.cc b/deps/v8/src/objects/lookup.cc
index 235a5547626534..9ec1f7fa2a04bf 100644
--- a/deps/v8/src/objects/lookup.cc
+++ b/deps/v8/src/objects/lookup.cc
@@ -1518,8 +1518,8 @@ base::Optional<PropertyCell> ConcurrentLookupIterator::TryGetPropertyCell(
   DisallowGarbageCollection no_gc;
 
   Map holder_map = holder->map();
-  CHECK(!holder_map.is_access_check_needed());
-  CHECK(!holder_map.has_named_interceptor());
+  if (holder_map.is_access_check_needed()) return {};
+  if (holder_map.has_named_interceptor()) return {};
 
   GlobalDictionary dict = holder->global_dictionary(kAcquireLoad);
   base::Optional<PropertyCell> cell =
diff --git a/doc/changelogs/CHANGELOG_V16.md b/doc/changelogs/CHANGELOG_V16.md
index b178b036380baf..128467175d01df 100644
--- a/doc/changelogs/CHANGELOG_V16.md
+++ b/doc/changelogs/CHANGELOG_V16.md
@@ -10,6 +10,7 @@
 </tr>
 <tr>
 <td>
+<a href="#16.9.1">16.9.1</a><br/>
 <a href="#16.9.0">16.9.0</a><br/>
 <a href="#16.8.0">16.8.0</a><br/>
 <a href="#16.7.0">16.7.0</a><br/>
@@ -46,6 +47,17 @@
   * [io.js](CHANGELOG_IOJS.md)
   * [Archive](CHANGELOG_ARCHIVE.md)
 
+<a id="16.9.1"></a>
+## 2021-09-10, Version 16.9.1 (Current), @richardlau
+
+### Notable Changes
+
+This release fixes a [regression](https://github.com/nodejs/node/issues/40030) introduced by the V8 9.3 update in Node.js 16.9.0.
+
+### Commits
+
+* [[`04f1943109`](https://github.com/nodejs/node/commit/04f1943109)] - **deps**: V8: cherry-pick 9a607043cb31 (Jiawen Geng) [#40046](https://github.com/nodejs/node/pull/40046)
+
 <a id="16.9.0"></a>
 ## 2021-09-07, Version 16.9.0 (Current), @targos
 
diff --git a/src/node_version.h b/src/node_version.h
index c1050d02345b5f..48b8d9f22fb98d 100644
--- a/src/node_version.h
+++ b/src/node_version.h
@@ -29,7 +29,7 @@
 #define NODE_VERSION_IS_LTS 0
 #define NODE_VERSION_LTS_CODENAME ""
 
-#define NODE_VERSION_IS_RELEASE 0
+#define NODE_VERSION_IS_RELEASE 1
 
 #ifndef NODE_STRINGIFY
 #define NODE_STRINGIFY(n) NODE_STRINGIFY_HELPER(n)