Correct a few things I missed from the advisories and add Thunderbird's

announce/2021/mfsa2021-07.yml

@@ -70,11 +70,11 @@ advisories:
     bugs:
       - url: 1683536
   CVE-2021-23975:
-    title: 'about:memory’s Measure function caused an incorrect pointer operation'
+    title: about:memory Measure function caused an incorrect pointer operation
     impact: low
     reporter: Brian Carpenter of Geeknik Labs & Farm
     description: |
-      The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When this function was invoked; we incorrectly called the sizeof function, instead of using the API method that checks for invalid pointers.
+      The developer page about:memory has a Measure function for exploring what object types the browser has allocated and their sizes. When this function was invoked we incorrectly called the sizeof function, instead of using the API method that checks for invalid pointers.
     bugs:
       - url: 1685145
   CVE-2021-23973:
@@ -97,7 +97,7 @@ advisories:
   CVE-2021-23979:
     title: Memory safety bugs fixed in Firefox 86
     impact: high
-    reporter: Mozilla developers and community
+    reporter: Mozilla developers
     description: |
       Mozilla developers Tyson Smith, Lars T Hansen, Valentin Gosu, and Sebastian Hengst reported memory safety bugs present in Firefox 85. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.
     bugs:

announce/2021/mfsa2021-08.yml

@@ -32,7 +32,7 @@ advisories:
   CVE-2021-23978:
     title: Memory safety bugs fixed in Firefox 86 and Firefox ESR 78.8
     impact: high
-    reporter: Mozilla developers and community
+    reporter: Mozilla developers
     description: |
       Mozilla developers Alexis Beingessner, Tyson Smith, Nika Layzell, and Mats Palmgren reported memory safety bugs present in Firefox 85 and Firefox ESR 78.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.
     bugs:

announce/2021/mfsa2021-09.yml

@@ -0,0 +1,42 @@
+## mfsa2021-09.yml
+announced: February 23, 2021
+impact: high
+fixed_in:
+- Thunderbird 78.8
+title: Security Vulnerabilities fixed in Thunderbird 78.8
+description: |
+  *In general, these flaws cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but are potentially risks in browser or browser-like contexts.*
+advisories:
+  CVE-2021-23969:
+    title: Content Security Policy violation report could have contained the destination of a redirect
+    impact: high
+    reporter: Masato Kinugawa
+    description: |
+      As specified in the W3C Content Security Policy draft, when creating a violation report, "User agents need to ensure that the source file is the URL requested by the page, pre-redirects. If that’s not possible, user agents need to strip the URL down to an origin to avoid unintentional leakage." Under certain types of redirects, Thunderbird incorrectly set the source file to be the destination of the redirects. This was fixed to be the redirect destination's origin.
+    bugs:
+      - url: 1542194
+  CVE-2021-23968:
+    title: Content Security Policy violation report could have contained the destination of a redirect
+    impact: high
+    reporter: Ademar Nowasky Junior
+    description: |
+      If Content Security Policy blocked frame navigation, the full destination of a redirect served in the frame was reported in the violation report; as opposed to the original frame URI. This could be used to leak sensitive information contained in such URIs.
+    bugs:
+      - url: 1687342
+  CVE-2021-23973:
+    title: MediaError message property could have leaked information about cross-origin resources
+    impact: low
+    reporter: Andreas Pehrson
+    description: |
+      When trying to load a cross-origin resource in an audio/video context a decoding error may have resulted, and the content of that error may have revealed information about the resource.
+    bugs:
+      - url: 1690976
+  CVE-2021-23978:
+    title: Memory safety bugs fixed in Thunderbird 78.8
+    impact: high
+    reporter: Mozilla developers
+    description: |
+      Mozilla developers Alexis Beingessner, Tyson Smith, Nika Layzell, and Mats Palmgren reported memory safety bugs present in Thunderbird 78.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.
+    bugs:
+      - url: 786797, 1682928, 1687391, 1687597
+        desc: Memory safety bugs fixed in Thunderbird 78.8