VULNERABILITY INTELLIGENCE

CVE-2026-4720

CVSS score9.8 CRITICAL
EPSS probability0.44%
CISA KEVNot currently listed
Published2026-03-24
Last modified2026-07-15
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Description

Memory safety bugs present in Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. 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, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Weakness classification

  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-120
  • 0b0ca135-0b70-47e7-9f44-1890c2a1c46c: CWE-120

Primary references