VulnerabilityAnalyzed

CVE-2026-30927

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.

MEDIUM 5.3EPSS 0.25%

Does this matter?

Lower severity and a low EPSS score (0.25%). Track it; it rarely justifies an emergency change on its own.

Description

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.

CVSS 4.0: 5.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.25% probability · 17th percentile
CISA KEV: Not listed
Weakness: CWE-639
Affected: admidio/admidio
Source: security-advisories@github.com

References

https://github.com/Admidio/admidio/commit/e47f70cc3cbcdb39635fdbaaef02d19f604b8c3ePatch
https://github.com/Admidio/admidio/issues/1985Issue Tracking
https://github.com/Admidio/admidio/security/advisories/GHSA-7pfv-hr63-h7cwMitigation, Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.