diff --git a/third_party/libwebm/README.libaom b/third_party/libwebm/README.libaom
index 16f1751..714f5d0 100644
--- a/third_party/libwebm/README.libaom
+++ b/third_party/libwebm/README.libaom
@@ -1,5 +1,5 @@
 URL: https://chromium.googlesource.com/webm/libwebm
-Version: dbf1d1089756e7cb5b1a04d6752310ef35912347
+Version: 81de00c43ea3c087b48a8c20337db7531b9f7612
 License: BSD
 License File: LICENSE.txt
 
diff --git a/third_party/libwebm/mkvparser/mkvparser.cc b/third_party/libwebm/mkvparser/mkvparser.cc
index dcb969d..ace65bd 100644
--- a/third_party/libwebm/mkvparser/mkvparser.cc
+++ b/third_party/libwebm/mkvparser/mkvparser.cc
@@ -4230,6 +4230,7 @@
         new (std::nothrow) ContentEncryption*[encryption_count];
     if (!encryption_entries_) {
       delete[] compression_entries_;
+      compression_entries_ = NULL;
       return -1;
     }
     encryption_entries_end_ = encryption_entries_;
@@ -4261,6 +4262,7 @@
         delete compression;
         return status;
       }
+      assert(compression_count > 0);
       *compression_entries_end_++ = compression;
     } else if (id == libwebm::kMkvContentEncryption) {
       ContentEncryption* const encryption =
@@ -4273,6 +4275,7 @@
         delete encryption;
         return status;
       }
+      assert(encryption_count > 0);
       *encryption_entries_end_++ = encryption;
     }
 
@@ -4325,6 +4328,12 @@
         return status;
       }
 
+      // There should be only one settings element per content compression.
+      if (compression->settings != NULL) {
+        delete[] buf;
+        return E_FILE_FORMAT_INVALID;
+      }
+
       compression->settings = buf;
       compression->settings_len = buflen;
     }