#VU74832 Security features bypass in Mozilla Firefox and Firefox ESR - CVE-2023-29542

Vulnerability identifier: #VU74832

Vulnerability risk: Medium

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

CVE-ID: CVE-2023-29542

CWE-ID: CWE-254

Exploitation vector: Network

Exploit availability: No

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

Vendor: Mozilla

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to improper handling of newline in a filename. A remote attacker can bypass the file extension security mechanisms that replaces dangerous file extensions such as .lnk with .download and potentially compromise the affected system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 100.0 - 111.0.1

Firefox ESR: 102.0 - 102.9.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2023-13/
https://www.mozilla.org/en-US/security/advisories/mfsa2023-14/

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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.