#VU46020 Spoofing attack in Mozilla Firefox - CVE-2020-15665

Vulnerability identifier: #VU46020

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-15665

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 Firefox does not reset the address bar after the beforeunload dialog is  shown if the user chooses to remain on the page. As a result, an incorrect URL is shown in the address bar.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 70.0 - 79.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2020-36/

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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.