Critical severity · published Jul 2, 2021
CVE-2021-36126
An issue was discovered in the AbuseFilter extension in MediaWiki through 1.36
9.8
CVSS
1.2%
EPSS
No
On KEV
Description
An issue was discovered in the AbuseFilter extension in MediaWiki through 1.36. If the MediaWiki:Abusefilter-blocker message is invalid within the content language, the filter user falls back to the English version, but that English version could also be invalid on a wiki. This would result in a fatal error, and potentially fail to block or restrict a potentially nefarious user.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 68% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ME
Mediawiki · Mediawiki
through 1.36 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-36126
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-36126
Patch
https://gerrit.wikimedia.org/r/q/I9e9f44b7663e810de70fb9ac7f6760f83dd4895b
Exploit
https://phabricator.wikimedia.org/T284364
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