Mozilla Firefox fixes a critical vulnerability

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[TLP:CLEAR] Mozilla Firefox fixes a critical vulnerability

Mozilla fixes a critical vulnerability in Firefox for Windows [1]. Products and their fixes [1]: Firefox - 136.0.4 Firefox ESR - 115.21.1, 128.8.1

Mozilla Firefox, Firefox ESR - sandbox escape (CVE-2025-2857)

CVSS 10.0 (Critical)

An unauthenticated remote attacker can exploit a flaw in the inter-process communication (IPC) mechanism in the Firefox browser for Windows to gain unauthorized access, which may lead to a sandbox escape [1].

The vulnerability is present in products:

Firefox; >136.0.4
Firefox ESR; >128.8.1; >115.21.1

CVSS: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

More information:

CVE-2025-2857 at cve.org, NVD
CWE-732: Incorrect Permission Assignment for Critical Resource at cwe.mitre.org

The vulnerability was publicly disclosed 27. 3. 2025.

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[TLP:CLEAR] Mozilla Firefox fixes a critical vulnerability

Mozilla Firefox, Firefox ESR - sandbox escape (CVE-2025-2857)

CVSS 10.0 (Critical)

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