#VU25855 Input validation error in Mozilla Firefox and Firefox ESR - CVE-2020-6811

Vulnerability identifier: #VU25855

Vulnerability risk: Low

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:Clear]

CVE-ID: CVE-2020-6811

CWE-ID: CWE-20

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 execute arbitrary OS commands.

The vulnerability exists due to insufficient validation of user-supplied input copied into buffer via the 'Copy as cURL' feature of Devtools' network tab. A remote attacker can trick the victim into using the 'Copy as cURL' feature to copy malicious data into buffer and later insert them into a terminal window.

Successful exploitation of the vulnerability may result in OS command execution.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 65.0 - 73.0.1

Firefox ESR: 60.0 - 60.9.0, 68.0 - 68.5.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2020-08/
https://www.mozilla.org/en-US/security/advisories/mfsa2020-09/
https://bugzilla.mozilla.org/show_bug.cgi?id=1607742

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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.