#VU28533 Spoofing attack in Mozilla Firefox - CVE-2020-12409

Vulnerability identifier: #VU28533

Vulnerability risk: Medium

CVSSv4.0: 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:P/U:Green]

CVE-ID: CVE-2020-12409

CWE-ID: CWE-451

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 incorrect processing of certain blank characters in URL in unicode that were rendered as space instead of an encoded URL. A remote attacker can use a specially crafted URL to spoof page content of legitimate website.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 70.0 - 76.0.1

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External links
http://www.mozilla.org/en-US/security/advisories/mfsa2020-20/
http://bugzilla.mozilla.org/show_bug.cgi?id=1629506

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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. However, proof of concept for this vulnerability is available.