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SOC/SIEM Consultancy

Sandbox escape due to incorrect boundary conditions in the WebRTC: Networking component. This vulnerability was fixed in Firefox ESR 140.10.1.
Published:
27 April 2026 at 22:00:00
Alert date:
28 April 2026 at 21:20:20
Source:
nvd.nist.gov
Web Technologies
A sandbox escape vulnerability exists in Firefox's WebRTC Networking component due to incorrect boundary conditions. This security flaw allows attackers to break out of Firefox's security sandbox, potentially leading to system compromise. The vulnerability affects Firefox ESR versions prior to 140.10.1. Mozilla has addressed this issue in Firefox ESR 140.10.1. The vulnerability has been assigned CVE-2026-7321 and is considered high severity due to its sandbox escape capabilities.
Technical details
Mitigation steps:
Affected products:
Firefox ESR
Related links:
https://nvd.nist.gov/vuln/detail/CVE-2026-7321
https://bugzilla.mozilla.org/show_bug.cgi?id=2029461
https://www.mozilla.org/security/advisories/mfsa2026-36/
Related CVE's:
Related threat actors:
IOC's:
This article was created with the assistance of AI technology by Perceptive.
