#VU110700 Buffer overflow in Mozilla Firefox - CVE-2025-49709

Vulnerability identifier: #VU110700

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-49709

CWE-ID: CWE-119

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mozilla Firefox
Client/Desktop applications / Web browsers

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in canvas surfaces when processing HTML content. A remote attacker can trick the victim into opening a specially crafted web page, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 130.0 - 139.0.1

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2025-47/
https://bugzilla.mozilla.org/show_bug.cgi?id=1966083

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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.