Privilege Escalation Vulnerabilities in Appointment Booking Calendar Plugin for WordPress
CVE-2016-20084

5.1MEDIUM

Key Information:

Vendor

WordPress
Status
Booking Calendar Contact
Vendor
CVE Published:
15 June 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2016-20084?

The Appointment Booking Calendar plugin for WordPress version 1.1.24 is susceptible to multiple vulnerabilities that could allow unauthenticated attackers to escalate privileges. Through manipulation of parameters in the admin.php file, attackers can modify calendar settings and inject persistent cross-site scripting (XSS) payloads. Malicious JavaScript can be injected via GET requests into specific settings, enabling the execution of arbitrary scripts whenever the calendar is accessed in the administrative interface, posing significant security risks.

Affected Version(s)

Booking Calendar Contact 0 <= 1.1.24

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2016-20084 - Proof of Concept

References

https://www.exploit-db.com/exploits/39341
exploit
http://wordpress.dwbooster.com/calendars/booking-calendar...
product
https://www.vulncheck.com/advisories/wordpress-appointmen...
third-party-advisory

CVSS V4

Score:
5.1
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Joaquin Ramirez Martinez [ i0 security-lab]
.