CVE-2026-110031: Salon Booking System Privilege Escalation

CVE-2026-110031 Overview

CVE-2026-110031 is a privilege escalation vulnerability in the Salon Booking System WordPress plugin versions prior to 10.31.11. The plugin fails to prevent users holding the custom salon staff role from assigning arbitrary WordPress capabilities to other accounts through the customer editing function. An authenticated attacker with the salon staff role can escalate any account, including their own, to administrator and achieve full site takeover. The flaw is classified under CWE-269: Improper Privilege Management.

Critical Impact
An authenticated salon staff user can grant administrator capabilities to any WordPress account, resulting in complete compromise of the affected site.

Affected Products

Salon Booking System WordPress plugin versions before 10.31.11
WordPress sites running the plugin with the custom salon staff role enabled
All downstream environments depending on the vulnerable plugin version

Discovery Timeline

2026-10-18 - CVE-2026-110031 published to the National Vulnerability Database (NVD)
2026-10-19 - Last updated in NVD database

Technical Details for CVE-2026-110031

Vulnerability Analysis

The Salon Booking System plugin introduces a custom WordPress role named salon staff for managing bookings and customer records. The customer edit workflow accepts capability parameters without validating whether the acting user is authorized to assign them. A salon staff user can submit a crafted request that attaches arbitrary capabilities, including administrator level privileges, to any WordPress account.

The flaw aligns with CWE-269 because privilege assignment logic trusts input from a lower-privileged role. The plugin does not restrict which capabilities salon staff can delegate, nor does it enforce a capability hierarchy during customer edit operations. Once an account is promoted, the attacker inherits full site administration, including plugin installation, user management, and content modification.

Root Cause

The root cause is missing authorization checks on the capability assignment path in the customer edit handler. The plugin accepts role or capability fields in the request payload and applies them without verifying that the requesting user holds the promote_users or equivalent administrative capability.

Attack Vector

Exploitation requires an authenticated session with the salon staff role. The attacker navigates to the customer edit interface and submits a modified request that assigns administrator capabilities to a target account. The attack vector is network-based, the complexity is low, and no user interaction is required beyond the attacker's own authenticated session. Refer to the WPScan Vulnerability Report for additional technical context.

Detection Methods for CVE-2026-110031

Indicators of Compromise

Unexpected changes to the wp_usermeta table where meta_key = wp_capabilities shows new administrator entries
WordPress audit log entries showing role modifications initiated by salon staff accounts
Creation of new administrator accounts shortly after salon staff login events
Installation of unfamiliar plugins or themes following suspicious user edit activity

Detection Strategies

Query the WordPress user database for accounts whose capabilities were elevated to administrator within the exposure window
Review HTTP request logs for POST requests to Salon Booking System customer edit endpoints containing capability or role parameters
Correlate salon staff authentication events with subsequent privileged actions such as plugin installation

Monitoring Recommendations

Enable a WordPress activity logging plugin to capture role and capability changes with user attribution
Forward web server access logs and WordPress audit events to a centralized SIEM for correlation
Alert on any role promotion event where the actor is not an existing administrator

How to Mitigate CVE-2026-110031

Immediate Actions Required

Update the Salon Booking System plugin to version 10.31.11 or later on all WordPress sites
Audit all WordPress accounts and remove unauthorized administrator privileges
Review the salon staff user list and disable any accounts that are no longer required
Rotate credentials for all administrator accounts after patching

Patch Information

The vendor addressed the vulnerability in Salon Booking System version 10.31.11. The fix enforces authorization checks on the customer edit workflow and prevents salon staff users from assigning capabilities they do not themselves hold. Site administrators should apply the update through the WordPress plugin manager or via WP-CLI. See the WPScan Vulnerability Report for vendor references.

Workarounds

Temporarily revoke the salon staff role from all accounts until the patch is applied
Restrict access to the WordPress admin interface by IP allowlist at the web server or WAF layer
Deploy a web application firewall rule that blocks role or capability parameters on customer edit requests

bash

# Update Salon Booking System via WP-CLI
wp plugin update salon-booking-system --version=10.31.11

# Verify installed version
wp plugin get salon-booking-system --field=version

# List accounts with administrator role for audit
wp user list --role=administrator --fields=ID,user_login,user_email,user_registered