Holiday class post calendar <= 7.1 - Unauthenticated Remote Code Execution via 'contents'

Improper Control of Generation of Code ('Code Injection')
CVE CVE-2025-12813
CVSS Critical (9.8)
Publicly Published November 10, 2025
Last Updated December 11, 2025
Researcher kr0d
Description

The Holiday class post calendar plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 7.1 via the 'contents' parameter. This is due to a lack of sanitization of user-supplied data when creating a cache file. This makes it possible for unauthenticated attackers to execute code on the server.

References

1 affected software package

Software Type Plugin
Software Slug holiday-class-post-calendar (view on wordpress.org)
Patched? Yes
Affected Version
  • <= 7.1
Patched Version
  • 7.2
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