Use After Free Affecting thunderbird package, versions <1:91.2.1-1


Severity

Recommended
0.0
high
0
10

Snyk's Security Team recommends NVD's CVSS assessment. Learn more

Threat Intelligence

EPSS
1.59% (73rd percentile)

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  • Snyk IDSNYK-ECHOLATEST-THUNDERBIRD-18319210
  • published26 Jul 2026
  • disclosed3 Nov 2021

Introduced: 3 Nov 2021

CVE-2021-38496  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Echo:latest thunderbird to version 1:91.2.1-1 or higher.

NVD Description

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

During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.

CVSS Base Scores

version 3.1