#VU25121 Improper access control in Mozilla Firefox and Firefox ESR - CVE-2020-6797

Vulnerability identifier: #VU25121

Vulnerability risk: Medium

CVSSv4.0: 4.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-6797

CWE-ID: CWE-284

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 gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions imposed on extensions that are granted downloads.open permission. A remote attacker can bypass implemented security restrictions and launch or open arbitrary application on the system.

Note: the vulnerability affects Mac OSX users only.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 61.0 - 72.0.2

Firefox ESR: 60.0 - 60.9.0, 68.0 - 68.4.2

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2020-05/
https://www.mozilla.org/en-US/security/advisories/mfsa2020-06/

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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.