CVE-2025-2857 – Mozilla Firefox Vulnerability

Severity

High

Analysis Summary

CVE-2025-2857

Mozilla Firefox could allow a remote attacker to bypass security restrictions, caused by an incorrect handle. The attacker could confuse the parent process into leaking handles into unprivileged child processes. An attacker could exploit this vulnerability to escape the browser’s sandbox and execute arbitrary code on affected systems.

Impact

Security Bypass

Indicators of Compromise

CVE

CVE-2025-2857

Affected Vendors

Mozilla

Affected Products

Mozilla Firefox - 136.0.3
Mozilla Firefox ESR - 115.21.0
Mozilla Firefox ESR - 128.8.0

Remediation

Refer to Mozilla Security Advisory for patch, upgrade, or suggested workaround information.

Mozilla Security Advisory

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