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 v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
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
https://github.com/Admidio/admidio/security/advisories/GHSA-92g9-59rr-c3qg
https://www.vulncheck.com/advisories/admidio-before-5.0.17-event-guest-restriction-bypass-via-events-function-php

Configurations

No configuration.

History

27 Oct 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-27 14:16

Updated : 2026-10-27 14:16

NVD link : CVE-2026-117554

Mitre link : CVE-2026-117554

CVE.ORG link : CVE-2026-117554

JSON object : View

Products Affected

No product.

CWE

CWE-602

Client-Side Enforcement of Server-Side Security

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