CVE-2026-91109 (GCVE-0-2026-91109)
Vulnerability from cvelistv5
Published
2026-10-01 03:28
Modified
2026-10-03 15:42
Severity ?
6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Summary
The Simply Schedule Appointments plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.31 via the 'complete_group' parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with subscriber-level access and above, to disclose every co-booker's private per-appointment id_token (exposed as public_token) alongside their PII (name and email address), then use each leaked token to read, overwrite arbitrary appointment meta on, or cancel the co-booker's appointment via the same REST controller. Exploitation requires the attacker to possess a valid id_token for any single appointment within the targeted group booking.
References
Impacted products
Vendor Product Version
croixhaug Simply Schedule Appointments Version: 0   ≤ 1.6.12.31
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