CVE-2021-29964 - CVE House
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Status published High CVE-2021-29964

A locally-installed hostile program could send `WM_COPYDATA` messages that Firefox...

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Thunderbird, Firefox, Firefox ESR
Vulnerable Versions:
unspecified

Timeline

Official Publish: June 24th, 2021
Last Modified: August 3rd, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.