CVE-2026-12378

CVE-2026-12378 is a high-severity vulnerability with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

The Appointment Booking Calendar Plugin and Scheduling Plugin WordPress plugin through 1.1.28 does not validate data before passing it to a PHP deserialization function, allowing unauthenticated attackers to inject arbitrary PHP objects; where a suitable gadget chain is present on the site this can be leveraged to achieve remote code execution.

Frequently asked questions

What is CVE-2026-12378?
The Appointment Booking Calendar Plugin and Scheduling Plugin WordPress plugin through 1.1.28 does not validate data before passing it to a PHP deserialization function, allowing unauthenticated attackers to inject arbitrary PHP objects; where a suitable gadget chain is present on the site this can be leveraged to achieve remote code execution.
How severe is CVE-2026-12378?
CVE-2026-12378 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-12378 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-12378?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-12378 published?
CVE-2026-12378 was published on 2026-07-08.

References