Vulnerability in MediaWiki Checkuser

CVE-2023-37252

An issue was discovered in the CheckUser extension for MediaWiki through 1.39.3. Special:CheckUserLog shows usernames that have been hidden.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (15.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2023-37252: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: -0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-37252?
CVE-2023-37252 is a low-severity vulnerability in MediaWiki Checkuser, classified under Incorrect Resource Transfer Between Spheres. CVSS score: 3.1/10. Published 2026-09-14.
How severe is CVE-2023-37252?
Low severity. CVSS v3 base score is 3.1 out of 10.