#VU54499 Improper access control in MediaWiki - CVE-2021-35197

Vulnerability identifier: #VU54499

Vulnerability risk: Low

CVSSv4.0: 0.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-35197

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 to purge pages for blocked user accounts. A remote user with a blocked account can purge pages.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

MediaWiki: 1.31.0 - 1.36.0

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External links
https://lists.wikimedia.org/hyperkitty/list/mediawiki-announce@lists.wikimedia.org/thread/YR3X4L2CPSEJVSY543AWEO65TD6APXHP/
https://phabricator.wikimedia.org/T280226
https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/core/+/7fc84bbd23c1205e13c7a8332ab39e6ff52ca107%5E%21/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.