CVE-2026-16401 — HIGH (8.8)

Q: What is CVE-2026-16401?

CVE-2026-16401 is a vulnerability with a CVSS score of 8.8 (HIGH). Privilege escalation in the Data Loss Prevention component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

Q: How severe is CVE-2026-16401?

CVE-2026-16401 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2026-16401?

Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.

Vulnerability Description

Privilege escalation in the Data Loss Prevention component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

CVSS Score

8.8

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

UNCHANGED

Confidentiality

HIGH

Integrity

HIGH

Availability

HIGH

Affected Products

Vendor	Product	Versions
Mozilla	Firefox	< 153.0.0
Mozilla	Thunderbird	< 153.0

Related Weaknesses (CWE)

CWE-269

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2052565Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-68/Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-71/Vendor Advisory

FAQ

What is CVE-2026-16401?

CVE-2026-16401 is a vulnerability with a CVSS score of 8.8 (HIGH). Privilege escalation in the Data Loss Prevention component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

How severe is CVE-2026-16401?

CVE-2026-16401 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-16401?

Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.