Home/CVE/An issue was discovered in the CheckUser extension for MediaWiki through 1.35.2. MediaWiki usernames with trailing white
CVE

CVE-2021-31553

An issue was discovered in the CheckUser extension for MediaWiki through 1.35.2. MediaWiki usernames with trailing white

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.

MEDIUM · CVSS 6.5 EPSS 0.00672
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-428Unquoted Search Path or Element
▤

Affected Products & Versions

1
mediawiki<= 1.35.2
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD22 Apr 2021 · 03:15 AM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
🔗

References & Sources

7
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/666963Issue TrackingThird Party Advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/666964Issue TrackingThird Party Advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667023Issue TrackingThird Party Advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667024Issue TrackingThird Party Advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667025Issue TrackingThird Party Advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667027Issue TrackingThird Party Advisory
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