CVE-2026-84121 Affecting thunderbird-debuginfo package, versions <0:140.16.0-1.el8_10


Severity

Recommended
high

Based on Rocky Linux security rating.

Threat Intelligence

EPSS
0.32% (25th percentile)

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  • Snyk IDSNYK-ROCKY8-THUNDERBIRDDEBUGINFO-20378327
  • published2 Oct 2026
  • disclosed1 Sept 2026

Introduced: 1 Sep 2026

CVE-2026-84121  (opens in a new tab)

How to fix?

Upgrade Rocky-Linux:8 thunderbird-debuginfo to version 0:140.16.0-1.el8_10 or higher.
This issue was patched in RLSA-2026:73971.

NVD Description

Note: Versions mentioned in the description apply only to the upstream thunderbird-debuginfo package and not the thunderbird-debuginfo package as distributed by Rocky-Linux. See How to fix? for Rocky-Linux:8 relevant fixed versions and status.

Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.

CVSS Base Scores

version 3.1