Auth bypass in Admidio
CVE-2026-30927
Admidio is an open-source user management solution. Prior to 5.0.6, in modules/events/events_function.php, the event participation logic allows any user who can participate in an event to register OTHER users by manipulating the user_uuid GET parameter. The condition uses || (OR), meaning if possibleToParticipate() returns true (event is open for participation), ANY user - not just leaders - can specify a different user_uuid and register/cancel participation for that user. The code then operates on $user->getValue('usr_id') (the target user from user_uuid) rather than the current user. This vulnerability is fixed in 5.0.6.
Vulnerability class: IDOR (Insecure Direct Object Reference)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
EPSS: 0.004 (26.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 26th percentile — 26.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.001
Affected products
- Admidio — versions < 5.0.6
Weakness classification (CWE)
References
- github.com/Admidio/admidio/security/advisories/GHSA-7pfv-hr63-h7cw (Mitigation, Vendor Advisory)
- github.com/Admidio/admidio/issues/1985 (Issue Tracking)
- github.com/Admidio/admidio/commit/e47f70cc3cbcdb39635fdbaaef02d19f604b8c3e (Patch)
Frequently asked questions
- What is CVE-2026-30927?
- CVE-2026-30927 is a medium-severity vulnerability in Admidio, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 5.4/10. Published 2026-03-10.
- How severe is CVE-2026-30927?
- Medium severity. CVSS v3 base score is 5.4 out of 10.