CVE-2025-1942 Affecting firefox-esr package, versions <136-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.46% (38th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-FIREFOXESR-17764989
  • published1 Jul 2026
  • disclosed4 Mar 2025

Introduced: 4 Mar 2025

CVE-2025-1942  (opens in a new tab)

How to fix?

Upgrade Chainguard firefox-esr to version 136-r0 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 Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

When String.toUpperCase() caused a string to get longer it was possible for uninitialized memory to be incorporated into the result string. This vulnerability was fixed in Firefox 136 and Thunderbird 136.

CVSS Base Scores

version 3.1