Auth bypass in Ameliabooking Booking For Appointments And Events Calendar – Amelia

CVE-2026-5465

The Booking for Appointments and Events Calendar – Amelia plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 2.1.3. This is due to the `UpdateProviderCommandHandler` failing to validate changes to the `externalId` field when a Provider (Employee) user updates their own profile. The `externalId` maps directly to a WordPress user ID and is passed to `wp_set_password()` and `wp_update_user()` without authorization checks. This makes it possible for authenticated attackers, with Provider-level (Employee) access and above, to take over any WordPress account — including Administrator — by injecting an arbitrary `externalId` value when updating their own provider profile.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.006 (44.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 44.7% 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-2026-5465: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: -0.001

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-5465?
CVE-2026-5465 is a high-severity vulnerability in Ameliabooking Booking For Appointments And Events Calendar – Amelia, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 8.8/10. Published 2026-04-07.
How severe is CVE-2026-5465?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2026-5465 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.