High severity · published Apr 22, 2021
CVE-2021-31555
An issue was discovered in the Oauth extension for MediaWiki through 1.35.2
7.5
CVSS
0.8%
EPSS
No
On KEV
Description
An issue was discovered in the Oauth extension for MediaWiki through 1.35.2. It did not validate the oarc_version (aka oauth_registered_consumer.oarc_version) parameter's length.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% 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-2021-31555
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31555
Issue Tracking
https://gerrit.wikimedia.org/r/q/I222c053b4b14ac1ad0f5b3a51565b1b9cd4c139d
Third Party Advisory
https://phabricator.wikimedia.org/T277388
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