diff --git a/pkgs/applications/networking/browsers/chromium/default.nix b/pkgs/applications/networking/browsers/chromium/default.nix
index e9e9961d1cd..7a3c387deda 100644
--- a/pkgs/applications/networking/browsers/chromium/default.nix
+++ b/pkgs/applications/networking/browsers/chromium/default.nix
@@ -81,6 +81,18 @@ let
     pre22 = stdenv.lib.versionOlder sourceInfo.version "22.0.0.0";
   in if pre22 then ./enable_seccomp.patch else ./enable_seccomp22.patch;
 
+  # XXX: this reverts r151720 to prevent http://crbug.com/143623
+  maybeRevertZlibChanges = let
+    below22 = stdenv.lib.versionOlder sourceInfo.version "22.0.0.0";
+    patch = fetchurl {
+      name = "revert-r151720";
+      url = "http://git.chromium.org/gitweb/?p=chromium.git;a=commitdiff_plain;"
+          + "hp=4419ec6414b33b6b19bb2e380b4998ed5193ecab;"
+          + "h=0fabb4fda7059a8757422e8a44e70deeab28e698";
+      sha256 = "0n0d6mkg89g8q63cifapzpg9dxfs2n6xvk4k13szhymvf67b77pf";
+    };
+  in stdenv.lib.optional (!below22) patch;
+
 in stdenv.mkDerivation rec {
   name = "${packageName}-${version}";
   packageName = "chromium";
@@ -114,7 +126,8 @@ in stdenv.mkDerivation rec {
 
   patches = stdenv.lib.optional (!config.selinux) seccompPatch
          ++ stdenv.lib.optional config.cups ./cups_allow_deprecated.patch
-         ++ stdenv.lib.optional config.pulseaudio ./pulseaudio_array_bounds.patch;
+         ++ stdenv.lib.optional config.pulseaudio ./pulseaudio_array_bounds.patch
+         ++ maybeRevertZlibChanges;
 
   postPatch = stdenv.lib.optionalString config.openssl ''
     cat $opensslPatches | patch -p1 -d third_party/openssl/openssl
diff --git a/pkgs/applications/networking/browsers/chromium/sources.nix b/pkgs/applications/networking/browsers/chromium/sources.nix
index 8ae373438f5..7d03c397bdc 100644
--- a/pkgs/applications/networking/browsers/chromium/sources.nix
+++ b/pkgs/applications/networking/browsers/chromium/sources.nix
@@ -1,18 +1,18 @@
 # This file is autogenerated from update.sh in the same directory.
 {
   dev = {
-    version = "23.0.1243.2";
-    url = "http://commondatastorage.googleapis.com/chromium-browser-official/chromium-23.0.1243.2.tar.bz2";
-    sha256 = "1idsc1k0c392mvh2rhfv0sr50rmzdab18ilh9p90mab5a6fk32rh";
+    version = "23.0.1255.0";
+    url = "http://commondatastorage.googleapis.com/chromium-browser-official/chromium-23.0.1255.0.tar.bz2";
+    sha256 = "12ks55mn6nahdzd5kgiwi9m2cfivb0pwj963g8d4kmdbw5bg017g";
   };
   beta = {
-    version = "22.0.1229.14";
-    url = "http://commondatastorage.googleapis.com/chromium-browser-official/chromium-22.0.1229.14.tar.bz2";
-    sha256 = "11z5wc1m5443bsassq3np79yqr2bwr06ph672by3saikl2xkadn5";
+    version = "22.0.1229.39";
+    url = "http://commondatastorage.googleapis.com/chromium-browser-official/chromium-22.0.1229.39.tar.bz2";
+    sha256 = "0v0yz9lkr9xdzh6660y9n2z8m1075ls2r3svafcfa80pq18chzfd";
   };
   stable = {
-    version = "21.0.1180.81";
-    url = "http://commondatastorage.googleapis.com/chromium-browser-official/chromium-21.0.1180.81.tar.bz2";
-    sha256 = "1b5svzg7xxx46bz9s5ayai2ig9b7s0x4s1yl7r42p9g27qwf0dpl";
+    version = "21.0.1180.89";
+    url = "http://commondatastorage.googleapis.com/chromium-browser-official/chromium-21.0.1180.89.tar.bz2";
+    sha256 = "1i9mjbjj3aywg03hd59m9j5gq5b5fl8nvw56g47q8s9k1bcsik0n";
   };
 }