Medium severity · published Apr 22, 2021
CVE-2021-31552
An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2
5.4
CVSS
0.6%
EPSS
No
On KEV
Description
An issue was discovered in the AbuseFilter extension for MediaWiki through 1.35.2. It incorrectly executed certain rules related to blocking accounts after account creation. Such rules would allow for user accounts to be created while blocking only the IP address used to create an account (and not the user account itself). Such rules could also be used by a nefarious, unprivileged user to catalog and enumerate any number of IP addresses related to these account creations.
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)0.6% · higher than 47% 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-2021-31552
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31552
Issue Tracking
https://gerrit.wikimedia.org/r/q/I8bae477ad7e4d0190335363ac2decf28e4313da1
Third Party Advisory
https://phabricator.wikimedia.org/T152394
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