Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Network-reachable authenticated action needing only a low-privileged Subscriber account (PR:L), no interaction, low complexity, yielding full admin-level control hence high C/I/A.
Primary rating from Vendor (Patchstack).
CVSS VectorVendor: Patchstack
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
2DescriptionCVE.org
Subscriber Privilege Escalation in WP BASE Booking <= 6.3.1 versions.
AnalysisAI
Privilege escalation in the WP BASE Booking WordPress plugin (versions 6.3.1 and earlier) lets a low-privileged authenticated Subscriber elevate their permissions to a higher-privileged role. Because the CVSS vector is AV:N/PR:L with high confidentiality, integrity, and availability impact, an attacker holding any low-level account - trivially obtained on sites with open registration - can gain administrative-level control over the booking system and potentially the wider WordPress instance. There is no public exploit identified at time of analysis, and the flaw is not listed in CISA KEV.
Technical ContextAI
The affected component is WP BASE Booking (marketed as 'WP BASE booking of appointments, services and events'), a WordPress appointment/booking plugin by developer Hakan Ozevin (CPE cpe:2.3:a:hakan_ozevin:wp_base_booking). The root cause is classified as CWE-266 (Incorrect Privilege Assignment), meaning the plugin grants a user more privileges than their assigned role should carry - typically caused by a plugin action, AJAX handler, or capability check that fails to properly validate the caller's role before performing privileged operations such as role/capability modification or accessing administrative functionality. In WordPress, Subscriber is the lowest built-in role and normally cannot manage content, users, or settings, so a defect that lets a Subscriber assume elevated capabilities effectively collapses the site's role-based access model.
RemediationAI
Upgrade WP BASE Booking to a version newer than 6.3.1 once the vendor publishes a fix; the supplied data does not name a confirmed patched release, so at time of analysis no vendor-released patched version is independently confirmed - check the Patchstack advisory (https://patchstack.com/database/wordpress/plugin/wp-base-booking-of-appointments-services-and-events/vulnerability/wordpress-wp-base-booking-plugin-6-3-1-privilege-escalation-vulnerability) and the plugin's WordPress.org page for the fixed version. Because exploitation requires a low-privileged account, an effective compensating control is to disable open user self-registration (uncheck 'Anyone can register' in WordPress Settings > General) or restrict the default new-user role, which removes the easy path to obtaining the Subscriber foothold at the cost of blocking legitimate self-service signups. Additionally, deploy a WordPress virtual-patching WAF (Patchstack or equivalent) to block the privilege-escalation request pattern, audit existing user accounts for unexpected role elevation, and consider deactivating the plugin until a patched version is available if the booking functionality is non-essential.
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Same weakness CWE-266 – Incorrect Privilege Assignment
View allSame technique Privilege Escalation
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-48194
GHSA-mgq4-mxf3-c87g