CVE-2026-117554

Admidio before 5.0.17 contains an improper access control vulnerability that allows authenticated members to register event guests by submitting the additional_guests field when guests are disallowed. Attackers can set additional_guests to the remaining seat count in modules/events/events_function.php to exhaust event capacity and block other members from registering.

CVSS 4.0

5.3CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

4.3CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

CWE

CWE-602

Published

2026-10-27

Modified

2026-10-27

Record from

the NVD, synced 2026-10-27

References

• https://github.com/Admidio/admidio
• https://github.com/Admidio/admidio/blob/v5.0.16/modules/events/events_function.php#L446-L462
• https://github.com/Admidio/admidio/commit/5b0ee3585d2a69a6e85fee00b7b93f3ebc1e44d9
• https://github.com/Admidio/admidio/issues/2231
• https://github.com/Admidio/admidio/releases/tag/v5.0.17

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