CVE-2026-86841: CWE-502 Deserialization of Untrusted Data in Online Scheduling and Appointment Booking System
The Online Scheduling and Appointment Booking System WordPress plugin before 28.3 does not prevent deserialization of untrusted input and does not correctly restrict a privileged maintenance feature to administrators, allowing users granted a custom booking-management capability, which an administrator must explicitly assign, to inject arbitrary PHP objects, overwrite privileged site options, and read stored integration secrets.
AI Analysis
Technical Summary
CVE-2026-86841 is a deserialization of untrusted data vulnerability (CWE-502) in the Online Scheduling and Appointment Booking System WordPress plugin versions from 23.2 up to but not including 28.3. The plugin improperly allows users granted a custom booking-management capability—assigned explicitly by an administrator—to inject arbitrary PHP objects via a maintenance feature that is insufficiently restricted. This can result in privilege escalation by overwriting sensitive site options and disclosure of stored integration secrets.
Potential Impact
An attacker with the custom booking-management capability can exploit this vulnerability to execute arbitrary PHP object injection, potentially leading to privilege escalation by overwriting privileged site options and unauthorized disclosure of sensitive integration secrets stored by the plugin.
Mitigation Recommendations
Upgrade the Online Scheduling and Appointment Booking System WordPress plugin to version 28.3 or later, where this vulnerability is fixed. Administrators should ensure that the custom booking-management capability is assigned only to trusted users until the update is applied.
CVE-2026-86841: CWE-502 Deserialization of Untrusted Data in Online Scheduling and Appointment Booking System
Description
The Online Scheduling and Appointment Booking System WordPress plugin before 28.3 does not prevent deserialization of untrusted input and does not correctly restrict a privileged maintenance feature to administrators, allowing users granted a custom booking-management capability, which an administrator must explicitly assign, to inject arbitrary PHP objects, overwrite privileged site options, and read stored integration secrets.
CVSS v3.1
Score 4.7medium
Affected software
Online Scheduling and Appointment Booking System
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-86841 is a deserialization of untrusted data vulnerability (CWE-502) in the Online Scheduling and Appointment Booking System WordPress plugin versions from 23.2 up to but not including 28.3. The plugin improperly allows users granted a custom booking-management capability—assigned explicitly by an administrator—to inject arbitrary PHP objects via a maintenance feature that is insufficiently restricted. This can result in privilege escalation by overwriting sensitive site options and disclosure of stored integration secrets.
Potential Impact
An attacker with the custom booking-management capability can exploit this vulnerability to execute arbitrary PHP object injection, potentially leading to privilege escalation by overwriting privileged site options and unauthorized disclosure of sensitive integration secrets stored by the plugin.
Mitigation Recommendations
Upgrade the Online Scheduling and Appointment Booking System WordPress plugin to version 28.3 or later, where this vulnerability is fixed. Administrators should ensure that the custom booking-management capability is assigned only to trusted users until the update is applied.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- WPScan
- Date Reserved
- 2026-09-08T14:44:08.802Z
- State
- PUBLISHED
Threat ID: 6ab8b2d5f7a7c54106aa92d8
Added to database: 09/27/2026, 06:08:21 UTC
Last enriched: 09/27/2026, 06:18:20 UTC
Last updated: 09/28/2026, 02:23:49 UTC
Views: 17
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