Out-of-bounds Write Affecting firefox-esr package, versions <140.6.0esr-1~deb12u1


Severity

Recommended
0.0
high
0
10

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

Threat Intelligence

EPSS
0.43% (36th percentile)

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  • Snyk IDSNYK-ECHOLATEST-FIREFOXESR-18169493
  • published22 Jul 2026
  • disclosed9 Dec 2025

Introduced: 9 Dec 2025

CVE-2025-14333  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Echo:latest firefox-esr to version 140.6.0esr-1~deb12u1 or higher.

NVD Description

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

Memory safety bugs present in Firefox ESR 140.5, Thunderbird ESR 140.5, Firefox 145 and Thunderbird 145. 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 was fixed in Firefox 146, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.

CVSS Base Scores

version 3.1