ChurchCRM: Username Enumeration via Differential Response in Public Login API

published 2026-04-17 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-23599

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 27%
public exploits: 0; none known

ChurchCRM is an open-source church management system. In versions prior to 7.2.0, the public API login endpoint (/api/public/user/login) returns distinguishable HTTP response codes based on whether a username exists: 404 for non-existent users and 401 for valid users with incorrect passwords. An unauthenticated attacker can exploit this difference to enumerate valid usernames, with no rate limiting or account lockout to impede the process. This issue has been fixed in version 7.2.0.

Patch / fix

links 2

github.com/ChurchCRM/CRM@214694e commit
github.com/ChurchCRM/CRM#8607 pull request

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 6 mo ago (2026-04-20)

Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 27% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

ChurchCRM CRM

Classification

Weakness

CWE-307 Improper Restriction of Excessive Authentication Attempts
CWE-204 Observable Response Discrepancy

References

Sources

CVE List CVE-2026-40485
NVD CVE-2026-40485

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary