Description
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.
Published: 2026-02-24
Score: 10 Critical
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

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Advisories
Source ID Title
Debian DLA Debian DLA DLA-4495-1 thunderbird security update
Debian DLA Debian DLA DLA-4496-1 firefox-esr security update
Debian DSA Debian DSA DSA-6152-1 thunderbird security update
History

Mon, 13 Apr 2026 14:30:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability affects Firefox < 148, Firefox ESR < 115.33, Firefox ESR < 140.8, Thunderbird < 148, and Thunderbird < 140.8. 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.

Mon, 02 Mar 2026 02:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Sat, 28 Feb 2026 04:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-119

Wed, 25 Feb 2026 16:30:00 +0000

Type Values Removed Values Added
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 10.0, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H'}


Wed, 25 Feb 2026 12:00:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Mozilla firefox Esr
Mozilla thunderbird
Vendors & Products Mozilla
Mozilla firefox
Mozilla firefox Esr
Mozilla thunderbird

Wed, 25 Feb 2026 00:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'}

threat_severity

Important


Tue, 24 Feb 2026 18:00:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability affects Firefox < 148, Firefox ESR < 115.33, and Firefox ESR < 140.8. Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability affects Firefox < 148, Firefox ESR < 115.33, Firefox ESR < 140.8, Thunderbird < 148, and Thunderbird < 140.8.
References

Tue, 24 Feb 2026 14:00:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software. This vulnerability affects Firefox < 148, Firefox ESR < 115.33, and Firefox ESR < 140.8.
Title Sandbox escape due to incorrect boundary conditions in the Telemetry component in External Software
References

Subscriptions

Mozilla Firefox Firefox Esr Thunderbird
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-04-13T13:52:48.532Z

Reserved: 2026-02-19T15:06:01.828Z

Link: CVE-2026-2776

cve-icon Vulnrichment

Updated: 2026-02-28T03:19:29.385Z

cve-icon NVD

Status : Modified

Published: 2026-02-24T14:16:26.023

Modified: 2026-04-13T15:17:24.590

Link: CVE-2026-2776

cve-icon Redhat

Severity : Important

Publid Date: 2026-02-24T13:33:12Z

Links: CVE-2026-2776 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-02-25T11:39:32Z

Weaknesses