Protection Mechanism Failure Affecting Firefox-ESR package, versions [,140.9.0)


Severity

Recommended
0.0
medium
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.46% (37th percentile)

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  • Snyk IDSNYK-UNMANAGED-FIREFOXESR-15762807
  • published24 Mar 2026
  • disclosed24 Mar 2026
  • creditpizzahunthack1

Introduced: 24 Mar 2026

CVE-2026-4700  (opens in a new tab)
CWE-693  (opens in a new tab)

How to fix?

Upgrade Firefox-ESR to version 140.9.0 or higher.

Overview

Affected versions of this package are vulnerable to Protection Mechanism Failure through the HTTP networking component. An attacker can bypass implemented mitigations by crafting specific HTTP requests.

CVSS Base Scores

version 4.0
version 3.1