CVE-2021-29967

HighCVSS 8.8/10Last modified Jun 17, 2026

Description

Mozilla developers reported memory safety bugs present in Firefox 88 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. This vulnerability affects Thunderbird < 78.11, Firefox < 89, and Firefox ESR < 78.11.

Metrics

CVSS 3.1 8.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-787

Affected software

No affected versions have been published.

Timeline

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

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