CVE-2026-2780 Affecting firefox-esr package, versions <140.8.0-r0


Severity

Recommended
0.0
critical
0
10

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Threat Intelligence

EPSS
0.34% (26th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-FIREFOXESR-17765254
  • published1 Jul 2026
  • disclosed24 Feb 2026

Introduced: 24 Feb 2026

CVE-2026-2780  (opens in a new tab)

How to fix?

Upgrade Chainguard firefox-esr to version 140.8.0-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.

Privilege escalation in the Netmonitor component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

CVSS Base Scores

version 3.1