Out-of-bounds Write Affecting firefox package, versions <0:140.9.1-1.el9_7.alma.1


Severity

Recommended
high

Based on AlmaLinux security rating.

Threat Intelligence

EPSS
0.33% (25th percentile)

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  • Snyk IDSNYK-ALMALINUX9-FIREFOX-16090147
  • published16 Apr 2026
  • disclosed16 Apr 2026

Introduced: 16 Apr 2026

CVE-2026-5734  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade AlmaLinux:9 firefox to version 0:140.9.1-1.el9_7.alma.1 or higher.
This issue was patched in ALSA-2026:7671.

NVD Description

Note: Versions mentioned in the description apply only to the upstream firefox package and not the firefox package as distributed by AlmaLinux. See How to fix? for AlmaLinux:9 relevant fixed versions and status.

Memory safety bugs present in Firefox ESR 140.9.0, Thunderbird ESR 140.9.0, Firefox 149.0.1 and Thunderbird 149.0.1. 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 149.0.2, Firefox ESR 140.9.1, Thunderbird 149.0.2, and Thunderbird 140.9.1.

CVSS Base Scores

version 3.1