Appointment Hour Booking <= 1.3.72 — CAPTCHA Bypass
CVE-2022-4036Published · Updated Action summary
Affected: ≤1.3.72Update to 1.3.73 or newer
All remediation steps- Severity
- Medium5.3
- CVSS
- 5.3CVSS 3.1 · CNA (Wordfence)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:NWhat does this vector mean?
AV:NAttack vector- Network
AC:LAttack complexity- Low
PR:NPrivileges required- None
UI:NUser interaction- None
S:UScope- Unchanged
C:LConfidentiality- Low
I:NIntegrity- None
A:NAvailability- None
- Weakness
- CWE-804 Guessable CAPTCHA
- Required access
- No account needed
- Exploit prediction (EPSS)
- No score
- CISA KEV
- Not listed
On this page8
Am I affected?
Appointment Hour Booking – Booking Calendar appointment-hour-booking
- Affected≤ 1.3.72
- Patched in1.3.73
Update to 1.3.73 or newer.
You are affected if you run ≤ 1.3.72. Version 1.3.73 and later are not affected by this issue.
- Check your version: in wp-admin go to Plugins → Installed Plugins and read the version under Appointment Hour Booking – Booking Calendar.
- No admin access? Run a passive check of your site. It reads public files only.
- No account is needed to exploit this. Treat any exposed site on an affected version as at risk.
What to do
- Update to version 1.3.73, or a newer patched version
- Rotate administrator passwords and application secrets if the site ran a vulnerable version while publicly reachable.
- Watch Appointment Hour Booking – Booking Calendar to get an email when the next vulnerability is published.
Advisory
Source description from Wordfence Intelligence, credited to Luca Greeb, Andreas Krüger.
The Appointment Hour Booking plugin for WordPress is vulnerable to CAPTCHA bypass in versions up to, and including, 1.3.72. This is due to the use of insufficiently strong hashing algorithm on the CAPTCHA secret that is also displayed to the user via a cookie.
Exploits & references
Proof-of-concept & detection
No public proof-of-concept or detection template is known for this vulnerability.
Advisories & patches
- Advisorywordfence.com
Related CVEs
More in Appointment Hour Booking – Booking Calendar
All 16| Severity | Vulnerability | CVE | Published |
|---|---|---|---|
| High7.2 | Unauthenticated Stored DOM-Based Cross-Site Scripting via Booking Form Single-Line Field via Schedule Calendar List Renderer ≤1.5.97Update to 1.5.98 | CVE-2026-96573 | |
| Medium5.3 | Unauthenticated Appointment Slot Capacity Bypass ≤1.5.94Update to 1.5.95 | CVE-2026-86475 | |
| Medium5.3 | Missing Authorization ≤1.5.94Update to 1.5.95 | CVE-2026-66679 | |
| Medium5.3 | Unauthenticated Price Manipulation ≤1.5.87Update to 1.5.88 | CVE-2026-16282 | |
| Medium6.4 | Authenticated (Contributor+) Stored Cross-Site Scripting ≤1.5.86Update to 1.5.87 | CVE-2026-65514 |
- High7.2Unauthenticated Stored DOM-Based Cross-Site Scripting via Booking Form Single-Line Field via Schedule Calendar List Renderer
≤1.5.97Update to 1.5.98
- Medium5.3Unauthenticated Appointment Slot Capacity Bypass
≤1.5.94Update to 1.5.95
- Medium5.3Missing Authorization
≤1.5.94Update to 1.5.95
- Medium5.3Unauthenticated Price Manipulation
≤1.5.87Update to 1.5.88
- Medium6.4Authenticated (Contributor+) Stored Cross-Site Scripting
≤1.5.86Update to 1.5.87
Timeline
CVE published
Severity medium, CVSS 5.3
Record last updated
Sources & licenses
Wordfence record- Vulnerability data
- Wordfence Intelligence. Copyright 2012-2026 Defiant Inc. Licensed under the CC BY-SA 4.0.
- CVE® identifiers
- Copyright 1999-2026 The MITRE Corporation. Used under the CVE Program. CVE® is a registered trademark of The MITRE Corporation.
- CVSS / CWE
- National Vulnerability Database (NVD), shown unmodified. This product uses the NVD API but is not endorsed or certified by the NVD.
- VulnCrest content
- Summary, remediation guidance and page layout © VulnCrest. Not sourced from NVD.