CVE-2026-4687

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

24/03/2026

Last modified:

13/04/2026

Description

Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.60 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Changed
Confidentiality (C): None
Integrity (I): None
Availability (A): High

Base Score 3.x

8.60

Severity 3.x

HIGH

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:mozilla:firefox:::::esr:::*		115.34.0 (excluding)
cpe:2.3:a:mozilla:firefox:::::-:::*		149.0 (excluding)
cpe:2.3:a:mozilla:firefox:::::esr:::*	128.0 (including)	140.9.0 (excluding)

To consult the complete list of CPE names with products and versions, see this page

CVE-2026-4687

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools