#VU29462 Insecure DLL loading in Mozilla Firefox - CVE-2020-12423

Vulnerability identifier: #VU29462

Vulnerability risk: Medium

CVSSv4.0: 4.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-12423

CWE-ID: CWE-427

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 compromise vulnerable system.

The vulnerability exists due to the application loads the "webauthn.dll" DLL library in an insecure manner. A remote attacker can place a specially crafted .dll file on a remote SMB fileshare, trick the victim into opening a file, associated with the vulnerable application, and execute arbitrary code on victim's system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 70.0 - 77.0.1

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2020-24/

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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.