#VU56982 Improper access control in MediaWiki - CVE-2021-41800

Vulnerability identifier: #VU56982

Vulnerability risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-41800

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
MediaWiki
Web applications / CMS

Vendor: MediaWiki.org

Description

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to improper access restrictions, related to PoolCounter and Special:Contributions section. A remote attacker can bypass implemented security restrictions and gain unauthorized access to the application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

MediaWiki: 1.30.0 - 1.36.1

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External links
https://lists.wikimedia.org/hyperkitty/list/mediawiki-announce@lists.wikimedia.org/thread/2IFS5CM2YV4VMSODPX3J2LFHKSEWVFV5/
https://phabricator.wikimedia.org/T284419

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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.