CVE-2021-31553

Description

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.67% Top 30%
Third-Party Advisory wikimedia.org Third-Party Advisory wikimedia.org Third-Party Advisory wikimedia.org Third-Party Advisory wikimedia.org Third-Party Advisory wikimedia.org Third-Party Advisory wikimedia.org Third-Party Advisory wikimedia.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://phabricator.wikimedia.org/T275669 third party advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667023 issue tracking third party advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667024 issue tracking third party advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667025 issue tracking third party advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/667027 issue tracking third party advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/666963 issue tracking third party advisory
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/CheckUser/+/666964 issue tracking third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-31553?
CVE-2021-31553 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31553?
To fix CVE-2021-31553, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-31553 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31553 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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