TrueBooker Appointment Booking < 1.2.7 - Unauthenticated Arbitrary Appointment Status Change via update_appointment_status (CVE-2026-18777) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-18777

TrueBooker Appointment Booking < 1.2.7 - Unauthenticated Arbitrary Appointment Status Change via update_appointment_status

Answer in brief

CVE-2026-18777 records a Unknown severity vulnerability in TrueBooker Appointment Booking < 1.2.7 - Unauthenticated Arbitrary Appointment Status Change via update_appointment_status. The current sources do not mark it as known exploited. The current feed maps Unknown/TrueBooker (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 19, 2026Updated Aug 19, 2026Source checked Aug 19, 2026First seen by HOL Aug 19, 2026Material review Aug 19, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Unknown/TrueBooker (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Unknown/TrueBookergeneric	>=0 <1.2.7	1.2.7

Recommended response

Check inventory. Check lockfiles and deployed manifests for Unknown/TrueBooker.
Review the reported fix. Update Unknown/TrueBooker to 1.2.7 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 19, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 19, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 19, 2026

Sources and claim methodology

Source referencewpscan.com

Upstream source description

The TrueBooker WordPress plugin before 1.2.7 does not have proper authorisation checks in one of its AJAX actions, allowing unauthenticated users to change the status of arbitrary appointments, as well as to trigger notification emails to the affected customers.

Quoted source text, attributed separately from HOL analysis.