cbcvebase.
CVE-2026-2776
published 2026-02-24

CVE-2026-2776: Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability was fixed in Firefox 148, Firefox ESR…

critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Affected

13 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 148.0-1 (sid)firefox 148.0-1 (sid)
debianfirefox-esr< firefox 148.0-1 (sid)firefox 148.0-1 (sid)
debianthunderbird< firefox 148.0-1 (sid)firefox 148.0-1 (sid)
mozillafirefox< 115.33.0115.33.0
mozillafirefox< 148.0148.0
mozillafirefox
mozillafirefox>= 128.0 < 140.8.0140.8.0
mozillathunderbird< 140.8.0140.8.0
mozillathunderbird< 148.0148.0
mozillathunderbird>= 0 < 1:140.8.0esr-1~deb11u11:140.8.0esr-1~deb11u1
mozillathunderbird>= 0 < 1:140.8.0esr-1~deb12u11:140.8.0esr-1~deb12u1
mozillathunderbird>= 0 < 1:140.8.0esr-1~deb13u11:140.8.0esr-1~deb13u1
mozillathunderbird>= 0 < 1:140.8.0esr-11:140.8.0esr-1

CVSS provenance

nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
osv10.0CRITICAL