CVE-2026-12378

BookingPress <= 1.5.5 - Unauthenticated PHP Object Injection

2026-06-17 00:00
Sanjar Tulkinov

Strategic Overview

Status
Unpatched
Affected Plugin
Appointment Booking Calendar Plugin and Scheduling Plugin – BookingPress
Affected Version
<= 1.5.5
CVSS
8.1High
Weakness type
CWE-502 · Deserialization of Untrusted Data
CVE
CVE-2026-12378
View all Appointment Booking Calendar Plugin and Scheduling Plugin – BookingPress vulnerabilities

At a glance

CVE-2026-12378 is a high-severity Deserialization of Untrusted Data vulnerability in the Appointment Booking Calendar Plugin and Scheduling Plugin WordPress plugin, affecting versions <= 1.5.5. It carries a CVSS score of 8.1 (reachable over the network; high confidentiality, integrity, availability impact). Exploitation requires no authentication. No fixed release has been reported yet; treat installations running this software as exposed. Disclosed June 2026, reported by Sanjar Tulkinov.

Vulnerability Overview

The BookingPress plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 1.5.5. This is due to deserialization of untrusted input. This makes it possible for unauthenticated attackers to inject a PHP Object. No known POP chain is present in the vulnerable software. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, and no privileges on the target site, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-502: Deserialization of Untrusted Data

Reaching this weakness in Appointment Booking Calendar Plugin and Scheduling Plugin <= 1.5.5 takes no account at all. Deserialization of untrusted data means the application reconstructs objects from input a caller controls, letting the attacker choose which classes get instantiated and what their properties hold.

A workable chain turns deserialization into file writes, deletions or code execution, depending on what the loaded classes do in their magic methods. No fixed build of this plugin is recorded for Appointment Booking Calendar Plugin and Scheduling Plugin yet, so installs running <= 1.5.5 stay exposed until the vendor ships one.

Remediation

No known patch available. Please review the vulnerability's details in depth and employ mitigations based on your organization's risk tolerance. It may be best to uninstall the affected software and find a replacement.

How does WordSec protect against this?

Requests carrying this pattern arrive without a session, so nothing upstream of the firewall gets a chance to reject them: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. No patched version is recorded yet, which is the case where a filtering layer matters most, because there is nothing to update to.

  • Firewall
  • Scanner
  • Login Security

External References

https://www.cve.org/CVERecord?id=CVE-2026-12378https://www.wordfence.com/threat-intel/vulnerabilities/id/16c99f2c-105d-4082-81ad-ffe1d970208dhttps://nvd.nist.gov/vuln/detail/CVE-2026-12378

Related records

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C