How severe is CVE-2023-45367?

CVE-2023-45367 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-45367 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-45367?

CVE-2023-45367 primarily affects Mediawiki. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-45367?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-45367 published?

CVE-2023-45367 was published on 2023-10-09 and last updated on 2026-06-17.

CVE-2023-45367

CVE-2023-45367 is a medium-severity vulnerability in Mediawiki with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mediawiki
Published: 2023-10-09
Last modified: 2026-06-17

Description

An issue was discovered in the CheckUser extension for MediaWiki before 1.35.12, 1.36.x through 1.39.x before 1.39.5, and 1.40.x before 1.40.1. A user can use a rest.php/checkuser/v0/useragent-clienthints/revision/ URL to store an arbitrary number of rows in cu_useragent_clienthints, leading to a denial of service.

Frequently asked questions

What is CVE-2023-45367?: An issue was discovered in the CheckUser extension for MediaWiki before 1.35.12, 1.36.x through 1.39.x before 1.39.5, and 1.40.x before 1.40.1. A user can use a rest.php/checkuser/v0/useragent-clienthints/revision/ URL to store an arbitrary number of rows in cu_useragent_clienthints, leading to a denial of service.
How severe is CVE-2023-45367?: CVE-2023-45367 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-45367 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-45367?: CVE-2023-45367 primarily affects Mediawiki. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-45367?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-45367 published?: CVE-2023-45367 was published on 2023-10-09 and last updated on 2026-06-17.

References

https://phabricator.wikimedia.org/T344923

Affected products (2)

cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:*
cpe:2.3:a:mediawiki:mediawiki:1.40.0:-:*:*:*:*:*:*

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