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Mozilla Foundation Security Advisory 2021-29

Security Vulnerabilities fixed in Firefox ESR 78.12

Announced
July 13, 2021
Impact
high
Products
Firefox ESR
Fixed in
  • Firefox ESR 78.12

#CVE-2021-29970: Use-after-free in accessibility features of a document

Reporter
Irvan Kurniawan
Impact
high
Description

A malicious webpage could have triggered a use-after-free, memory corruption, and a potentially exploitable crash.
This bug only affected Firefox when accessibility was enabled.

References

#CVE-2021-30547: Out of bounds write in ANGLE

Reporter
(Unknown)
Impact
high
Description

An out of bounds write in ANGLE could have allowed an attacker to corrupt memory leading to a potentially exploitable crash.

References

#CVE-2021-29976: Memory safety bugs fixed in Firefox 90 and Firefox ESR 78.12

Reporter
Mozilla developers
Impact
high
Description

Mozilla developers Valentin Gosu, Randell Jesup, Emil Ghitta, Tyson Smith, and Olli Pettay reported memory safety bugs present in Firefox 89 and Firefox ESR 78.11. 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