#VU106361 Processor optimization removal or modification of security-critical code in Mozilla Firefox and Firefox for Android - CVE-2025-3031

Vulnerability identifier: #VU106361

Vulnerability risk: Low

CVSSv4.0: 0.5 [CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-3031

CWE-ID: CWE-1037

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Firefox
Client/Desktop applications / Web browsers
Firefox for Android
Mobile applications / Apps for mobile phones

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to a JIT optimization error. A remote attacker can read 32 bits of values spilled onto the stack in a JIT compiled function.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 130.0 - 136.0.4

Firefox for Android: 130.0 - 136.0.1

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External links
https://bugzilla.mozilla.org/show_bug.cgi?id=1947141
https://www.mozilla.org/security/advisories/mfsa2025-20/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.