CVE-2021-29964

HighCVSS 7.1/10Last modified Jun 17, 2026

Description

A locally-installed hostile program could send `WM_COPYDATA` messages that Firefox would process incorrectly, leading to an out-of-bounds read. *This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 78.11, Firefox < 89, and Firefox ESR < 78.11.

Metrics

CVSS 3.1 7.1/10CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

Weakness enumeration

CWE-125

Affected software

Vendor	Product	Versions
Mozilla	Thunderbird	>= unspecified, < 78.11
Mozilla	Firefox	>= unspecified, < 89
Mozilla	Firefox ESR	>= unspecified, < 78.11

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1706501Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-23/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-24/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-26/Release Notes, Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1706501Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-23/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-24/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-26/Release Notes, Vendor Advisory

Timeline

Published: Jun 24, 2021
Last modified: Jun 17, 2026
NVD status: Modified

Related CVEs from 2021

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