Auth bypass in Masaakitanaka Booking Package

CVE-2026-9851

The Booking Package plugin for WordPress is vulnerable to Privilege Escalation via Account Takeover in versions up to, and including, 1.7.16. This is due to a missing capability check on the 'updateUser' branch of the package_app_action AJAX endpoint, where the handler only validates a nonce and the dispatcher invokes Schedule::updateUser() with the $administrator argument hard-coded to 1, bypassing the only owner-restriction check inside that function and allowing the target user to be determined solely by attacker-supplied input passed directly to wp_update_user(). This makes it possible for authenticated attackers, with Editor-level access and above, to change the email address and password of any account, including Administrator accounts, resulting in a full site takeover.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (47.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-9851: held from 0.004 to 0.006.

EPSS over last 30 days · oldest: 0.004 · newest: 0.006 · change: +0.003

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-9851?
CVE-2026-9851 is a high-severity vulnerability in Masaakitanaka Booking Package, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 7.2/10. Published 2026-06-06.
How severe is CVE-2026-9851?
High severity. CVSS v3 base score is 7.2 out of 10.