#VU49020 Permissions, Privileges, and Access Controls in Mozilla Firefox and Firefox ESR - CVE-2020-26978

Vulnerability identifier: #VU49020

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-26978

CWE-ID: CWE-264

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 access to sensitive information.

The vulnerability exists due to application does not properly impose security restrictions. A remote attacker can create a specially crafted webpage and send probes to hosts in internal network as well as to services on the user's local machine.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mozilla Firefox: 60.0 - 83.0

Firefox ESR: 60.0 - 60.9.0, 68.0 - 68.12.0, 78.0 - 78.5.0

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External links
https://www.mozilla.org/en-US/security/advisories/mfsa2020-54/
https://www.mozilla.org/en-US/security/advisories/mfsa2020-55/

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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.