#VU109859 Input validation error in Mozilla products - CVE-2025-5265

Vulnerability identifier: #VU109859

Vulnerability risk: Medium

CVSSv4.0: 4.5 [CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-5265

CWE-ID: CWE-20

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 compromise the affected system.

The vulnerability exists due to insufficient validation of user-supplied input within the "Copy as cURL" feature. A remote attacker can trick the victim into copying a specially crafted URL, trick the victim into using this command and execute arbitrary commands on the system.

The vulnerability affects Windows installations only.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 100.0 - 138.0.4

Firefox ESR: 102.0, 102.0.1, 102.1.0, 102.2.0, 102.3.0, 102.4.0, 102.5.0, 102.6.0, 102.7.0, 102.8.0, 102.9.0, 102.10.0, 102.11.0, 102.12.0, 102.13.0, 102.14.0, 102.15.0, 102.15.1, 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, 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

Firefox for Android: 100.1.0 - 138.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2025-43/
https://bugzilla.mozilla.org/show_bug.cgi?id=1962301
https://www.mozilla.org/en-US/security/advisories/mfsa2025-44/
https://www.mozilla.org/en-US/security/advisories/mfsa2025-42/

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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.