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

Vulnerability identifier: #VU106361

CSH Severity: Low

CVSS v4: 2.1 [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]

CVE-ID: CVE-2025-3031

CWE-ID: CWE-1037

Exploitation vector: Remote access

Exploit availability: No public exploit available

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.

Firefox for Android
Mozilla Firefox
Gentoo Linux
Ubuntu
Fedora
Mozilla Thunderbird
www-client/firefox
www-client/firefox-bin
mail-client/thunderbird
mail-client/thunderbird-bin
dev-lang/spidermonkey
firefox
thunderbird (Ubuntu package)

Install updates from vendor's website.

Firefox for Android - update to 137.0
Mozilla Firefox - update to 137.0
Mozilla Thunderbird - update to 137.0
www-client/firefox - update to 60.8.0
www-client/firefox-bin - update to 60.8.0
mail-client/thunderbird - update to 128.9.0
mail-client/thunderbird-bin - update to 128.9.0
dev-lang/spidermonkey - update to 128.9.0
firefox - addressed in versions 137.0-2.fc40, 137.0-2.fc41, 137.0-2.fc42
thunderbird (Ubuntu package) - update to 1:140.7.1+build1-0ubuntu0.22.04.1

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

• Multiple vulnerabilities in Mozilla Firefox and Firefox ESR
• Multiple vulnerabilities in Mozilla Thunderbird
• Fedora 41 update for firefox
• Fedora 40 update for firefox
• Fedora 42 update for firefox
• Gentoo update for Mozilla Firefox
• Gentoo update for Mozilla Thunderbird
• Gentoo update for Spidermonkey
• Ubuntu update for thunderbird