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Mozilla Foundation Security Advisory 2021-24

Security Vulnerabilities fixed in Firefox ESR 78.11

Announced
June 1, 2021
Impact
moderate
Products
Firefox ESR
Fixed in
  • Firefox ESR 78.11

#CVE-2021-29964: Out of bounds-read when parsing a "WM_COPYDATA" message

Reporter
Ronald Crane
Impact
moderate
Description

A locally-installed hostile program could send WM_COPYDATA messages that Firefox would processing incorrectly, leading to an out-of-bounds read.
This bug only affects Firefox on Windows. Other operating systems are unaffected.

References

#CVE-2021-29967: Memory safety bugs fixed in Firefox 89 and Firefox ESR 78.11

Reporter
Mozilla developers and community
Impact
high
Description

Mozilla developers Gabriele Svelto, Anny Gakhokidze, Alexandru Michis, Christian Holler reported memory safety bugs present in Firefox 88 and Firefox ESR 78.10. 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.

References