CVE-2026-4722
Published: 24 March 2026
Summary
CVE-2026-4722 is a high-severity an unspecified weakness vulnerability in Mozilla Firefox. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 4.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and AC-25 (Reference Monitor).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly addresses the CVE by requiring timely remediation through patching Firefox and Thunderbird to version 149 or later where the IPC privilege escalation flaw is fixed.
Enforces a reference monitor for access control decisions in IPC communications, mitigating unauthorized privilege escalations between browser processes.
Maintains process isolation in the browser to limit the scope and impact of IPC-based privilege escalation exploits.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
CVE explicitly describes a privilege escalation vulnerability in the browser IPC component (sandbox escape pattern), directly enabling T1068 Exploitation for Privilege Escalation via remote exploit with user interaction.
NVD Description
Privilege escalation in the IPC component. This vulnerability was fixed in Firefox 149 and Thunderbird 149.
Deeper analysisAI
CVE-2026-4722 is a privilege escalation vulnerability in the IPC component of Mozilla Firefox and Thunderbird. It affects versions of these browsers prior to 149, where the issue was addressed. Published on 2026-03-24, the vulnerability carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) and is associated with CWE category NVD-CWE-noinfo.
The vulnerability can be exploited by remote attackers requiring low attack complexity and no privileges, though user interaction is necessary. Successful exploitation enables high-impact consequences on confidentiality, integrity, and availability within the unchanged scope, allowing privilege escalation in the affected browser processes.
Mozilla's security advisories MFSA 2026-20 and MFSA 2026-23 detail the fix implemented in Firefox 149 and Thunderbird 149. Additional technical information is available in Bugzilla entry 2010097.
Details
- CWE(s)