CVE-2026-4700

Mitigation bypass in the Networking: HTTP component

Critical · published March 24, 2026

CVSS v3.1
9.8
EPSS
0%
Percentile
40.2
In the wild
Unconfirmed
What it is

Mitigation bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00476 · 40.2th percentile
Published
2026-03-24T12:30Z
EPSS history
Timeline
  • 24 MAR 12:30Z
    Mitigation bypass in the Networking: HTTP component
    cvelistv5