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

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
Mozilla Firefox affected
Version Status Constraints
unspecified affected
< 149
Mozilla Firefox ESR affected
Version Status Constraints
unspecified affected
< 115.34
Mozilla Firefox ESR affected
Version Status Constraints
unspecified affected
< 140.9
Mozilla Thunderbird affected
Version Status Constraints
unspecified affected
< 149
Mozilla Thunderbird affected
Version Status Constraints
unspecified affected
< 140.9

Configuration 1 [-]

OR cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*

No data.

No data.

Subscriptions

Vendors Products
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Firefox Subscribe

Tracking

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://bugzilla.mozilla.org/show_bug.cgi?id=2016368 cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-20/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-21/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-22/ cve-icon cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-23/ cve-icon
https://www.mozilla.org/security/advisories/mfsa2026-24/ cve-icon
History

Tue, 24 Mar 2026 20:30:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9. Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
References

Tue, 24 Mar 2026 19:30:00 +0000

Type Values Removed Values Added
First Time appeared Mozilla
Mozilla firefox
Weaknesses CWE-754
CPEs cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
Vendors & Products Mozilla
Mozilla firefox
Metrics cvssV3_1

{'score': 8.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}

Tue, 24 Mar 2026 12:45:00 +0000

Type Values Removed Values Added
Description Sandbox escape due to incorrect boundary conditions in the Telemetry component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, and Firefox ESR < 140.9.
Title Sandbox escape due to incorrect boundary conditions in the Telemetry component
References
cve-icon MITRE

Status: PUBLISHED

Assigner: mozilla

Published:

Updated: 2026-03-24T20:27:18.678Z

Reserved: 2026-03-23T23:21:35.819Z

Link: CVE-2026-4687

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2026-03-24T13:16:04.537

Modified: 2026-03-24T19:17:50.887

Link: CVE-2026-4687

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses