#VU57887 Input validation error in Mozilla Firefox

Vulnerability identifier: #VU57887

Vulnerability risk: Medium

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

CVE-ID: N/A

CWE-ID: CWE-20

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 perform spoofing attack.

The vulnerability exists due to insufficient validation of URL when parsing internationalized domain names. High bits of the characters in the URLs are sometimes stripped, resulting in inconsistencies that could lead to user confusion or attacks such as phishing.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 92.0 - 93.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2021-48/

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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.