Medium severity · published Apr 22, 2021
CVE-2021-31554
An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2
5.4
CVSS
0.5%
EPSS
No
On KEV
Description
An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. It improperly handled account blocks for certain automatically created MediaWiki user accounts, thus allowing nefarious users to remain unblocked.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ME
Mediawiki · Mediawiki
through 1.35.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31554
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31554
Issue Tracking
https://gerrit.wikimedia.org/r/q/Ie1f4333d5b1c9d17fb2236fe38a31de427a4cc48
Third Party Advisory
https://phabricator.wikimedia.org/T272244
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