CVE-2026-30927
Admidio: Event participation IDOR - non-leaders can register other users for events via user_uuid parameter
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
admidio/admidioReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | admidio/admidio | all versions | 5.0.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for admidio/admidio. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update admidio/admidio to 5.0.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30927 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-30927 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-30927. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-30927 in your dependencies?
O3 detects CVE-2026-30927 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.