#VU113139 NULL pointer dereference in Mozilla products - CVE-2025-8033

Vulnerability identifier: #VU113139

Vulnerability risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2025-8033

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

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

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in the JavaScript engine when handling closed generators. A remote attacker can trick the victim into visiting a specially crafted website and crash the browser. 

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 120.0 - 140.0.4

Firefox ESR: 115.0, 115.0.1, 115.0.2, 115.0.3, 115.1.0, 115.2.0, 115.2.1, 115.3.0, 115.3.1, 115.4.0, 115.5.0, 115.6.0, 115.7.0, 115.8.0, 115.9.0, 115.9.1, 115.10.0, 115.11.0, 115.12.0, 115.13.0, 115.14.0, 115.15.0, 115.16.0, 115.16.1, 115.17.0, 115.18.0, 115.19.0, 115.20.0, 115.21.0, 115.21.1, 115.22.0, 115.23.0, 115.23.1, 115.24.0, 115.25.0, 128.0, 128.1.0, 128.2.0, 128.3.0, 128.3.1, 128.4.0, 128.5.0, 128.5.1, 128.5.2, 128.6.0, 128.7.0, 128.8.0, 128.8.1, 128.9.0, 128.10.0, 128.10.1, 128.11.0, 128.12.0, 140.0

Firefox for Android: 120.0 - 140.0.4

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2025-57/
https://www.mozilla.org/en-US/security/advisories/mfsa2025-58/
https://www.mozilla.org/en-US/security/advisories/mfsa2025-59/
https://www.mozilla.org/en-US/security/advisories/mfsa2025-56/
https://bugzilla.mozilla.org/show_bug.cgi?id=1973990

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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.