CVE-2026-84640 Affecting thunderbird package, versions <0:140.16.0-1.el8_10


Severity

Recommended
high

Based on Rocky Linux security rating.

Threat Intelligence

EPSS
0.26% (17th percentile)

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  • Snyk IDSNYK-ROCKY8-THUNDERBIRD-20378385
  • published2 Oct 2026
  • disclosed1 Sept 2026

Introduced: 1 Sep 2026

CVE-2026-84640  (opens in a new tab)

How to fix?

Upgrade Rocky-Linux:8 thunderbird 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 package and not the thunderbird package as distributed by Rocky-Linux. See How to fix? for Rocky-Linux:8 relevant fixed versions and status.

A maliciously constructed mail header could lead to a one byte read past the end of a buffer. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.

CVSS Base Scores

version 3.1