VULNERABILITY INTELLIGENCE

CVE-2021-29967

CVSS score8.8 HIGH

EPSS probability1.37%

CISA KEVNot currently listed

Published2021-06-24

Last modified2026-06-17

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.