Use After Free Affecting Firefox-ESR package, versions [,115.34.0)[116.0.0,140.9.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.48% (39th percentile)

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  • Snyk IDSNYK-UNMANAGED-FIREFOXESR-15762805
  • published24 Mar 2026
  • disclosed24 Mar 2026
  • creditSota Wada

Introduced: 24 Mar 2026

CVE-2026-4696  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Firefox-ESR to version 115.34.0, 140.9.0 or higher.

Overview

Affected versions of this package are vulnerable to Use After Free in the Layout: Text and Fonts component. An attacker can execute arbitrary code or cause a denial of service by triggering a use-after-free condition during the rendering process.

CVSS Base Scores

version 4.0
version 3.1