diff --git a/packager/app/test/packager_test.py b/packager/app/test/packager_test.py
index 891d3999c1..3bd90625c5 100755
--- a/packager/app/test/packager_test.py
+++ b/packager/app/test/packager_test.py
@@ -139,6 +139,15 @@ class PackagerAppTest(unittest.TestCase):
     self._DiffGold(self.output[1], 'bear-640x360-v-cenc-golden.mp4')
     self._DiffGold(self.mpd_output, 'bear-640x360-av-cenc-golden.mpd')
 
+  def testPackageWebmWithEncryption(self):
+    self.packager.Package(
+        self._GetStreams(['video'],
+                         output_format='webm',
+                         test_files=['bear-640x360.webm']),
+        self._GetFlags(encryption=True))
+    self._DiffGold(self.output[0], 'bear-640x360-vp8-cenc-golden.webm')
+    self._DiffGold(self.mpd_output, 'bear-640x360-vp8-cenc-webm-golden.mpd')
+
   def testPackageHevcWithEncryption(self):
     self.packager.Package(
         self._GetStreams(['video'],
diff --git a/packager/app/test/testdata/bear-640x360-vp8-cenc-golden.webm b/packager/app/test/testdata/bear-640x360-vp8-cenc-golden.webm
new file mode 100644
index 0000000000..0111edcc04
Binary files /dev/null and b/packager/app/test/testdata/bear-640x360-vp8-cenc-golden.webm differ
diff --git a/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd b/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd
new file mode 100644
index 0000000000..914e633901
--- /dev/null
+++ b/packager/app/test/testdata/bear-640x360-vp8-cenc-webm-golden.mpd
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--Generated with https://github.com/google/edash-packager version <tag>-<hash>-<test>-->
+<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" xmlns:cenc="urn:mpeg:cenc:2013" minBufferTime="PT2S" type="static" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011" mediaPresentationDuration="PT2.7360000610351562S">
+  <Period id="0">
+    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="1000000/33000" par="16:9">
+      <Representation id="0" bandwidth="336974" codecs="vp8" mimeType="video/webm" sar="1:1">
+        <ContentProtection schemeIdUri="urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed" cenc:default_KID="31323334-3536-3738-3930-313233343536">
+          <cenc:pssh>AAAAMHBzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAABAxMjM0NTY3ODkwMTIzNDU2</cenc:pssh>
+        </ContentProtection>
+        <BaseURL>output_video.webm</BaseURL>
+        <SegmentBase indexRange="115195-115245" timescale="1000000">
+          <Initialization range="0-339"/>
+        </SegmentBase>
+      </Representation>
+    </AdaptationSet>
+  </Period>
+</MPD>
diff --git a/packager/mpd/base/mpd_utils.cc b/packager/mpd/base/mpd_utils.cc
index 2369969051..893a262d00 100644
--- a/packager/mpd/base/mpd_utils.cc
+++ b/packager/mpd/base/mpd_utils.cc
@@ -227,18 +227,20 @@ void AddContentProtectionElementsHelperTemplated(
   // (MP4) files.
   const bool is_mp4_container =
       media_info.container_type() == MediaInfo::CONTAINER_MP4;
+  std::string key_id_uuid_format;
+  if (protected_content.has_default_key_id()) {
+    if (!HexToUUID(protected_content.default_key_id(), &key_id_uuid_format)) {
+      LOG(ERROR) << "Failed to convert default key ID into UUID format.";
+    }
+  }
+
   if (is_mp4_container) {
     ContentProtectionElement mp4_content_protection;
     mp4_content_protection.scheme_id_uri = kEncryptedMp4Scheme;
     mp4_content_protection.value = kEncryptedMp4Value;
-    if (protected_content.has_default_key_id()) {
-      std::string key_id_uuid_format;
-      if (HexToUUID(protected_content.default_key_id(), &key_id_uuid_format)) {
-        mp4_content_protection.additional_attributes["cenc:default_KID"] =
-            key_id_uuid_format;
-      } else {
-        LOG(ERROR) << "Failed to convert default key ID into UUID format.";
-      }
+    if (!key_id_uuid_format.empty()) {
+      mp4_content_protection.additional_attributes["cenc:default_KID"] =
+          key_id_uuid_format;
     }
 
     parent->AddContentProtectionElement(mp4_content_protection);
@@ -269,6 +271,11 @@ void AddContentProtectionElementsHelperTemplated(
       drm_content_protection.subelements.push_back(cenc_pssh);
     }
 
+    if (!key_id_uuid_format.empty() && !is_mp4_container) {
+      drm_content_protection.additional_attributes["cenc:default_KID"] =
+          key_id_uuid_format;
+    }
+
     parent->AddContentProtectionElement(drm_content_protection);
   }