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.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-639"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/30xxx/CVE-2026-30927.json"
}{
"extracted_events": [
{
"cpe": "cpe:2.3:a:admidio:admidio:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "5.0.6"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "e47f70cc3cbcdb39635fdbaaef02d19f604b8c3e"
}
],
"source": "REFERENCES_COMMIT"
}
]
}