CVE-2021-31553
MEDIUM severity · CVSS 6.5 · CWE-428
6.5CVSS MEDIUM
Summary
An issue was discovered in the CheckUser extension for MediaWiki through 1.35.2. MediaWiki usernames with trailing whitespace could be stored in the cu_log database table such that denial of service occurred for certain CheckUser extension pages and functionality. For example, the attacker could turn off Special:CheckUserLog and thus interfere with usage tracking.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactNone
Integrity impactLow
Availability impactLow
Exploit probability (EPSS)1%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Affected products we track (1)
Recommendation
Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/666963Advisory
- https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/666964Advisory
- https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667023Advisory
- https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667024Advisory
- https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667025Advisory
- https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667027Advisory
- https://phabricator.wikimedia.org/T275669Advisory