The Uncanny Automator – Easy Automation, Integration, Webhooks & Workflow Builder Plugin plugin for WordPress is vulnerable to arbitrary file deletion due to insufficient file path validation in the fr_token function in all versions up to, and including, 7.3.1.4. This makes it possible for unauthenticated attackers to delete arbitrary files on the server, which can easily lead to remote code execution when the right file is deleted (such as wp-config.php). Exploitation requires a Forminator form connected to an Uncanny Automator recipe configured for Everyone, allowing unauthenticated form submissions to supply the malicious serialized payload; a gadget chain is present within the plugin via the Action_Helpers_Email __destruct() method, meaning no external gadget library is required.
Weakness
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Potential Mitigations
- Make fields transient to protect them from deserialization.
- An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.
Related Attack Patterns
References
- https://plugins.trac.wordpress.org/browser/uncanny-automator/tags/7.3.1.4/src/core/lib/recipe-parts/actions/trait-action-helpers-email.php#L481
- https://plugins.trac.wordpress.org/browser/uncanny-automator/tags/7.3.1.4/src/core/lib/utilities/db/class-automator-db-handler-triggers.php#L300
- https://plugins.trac.wordpress.org/browser/uncanny-automator/tags/7.3.1.4/src/core/services/email/attachment/handler.php#L201
- https://plugins.trac.wordpress.org/browser/uncanny-automator/tags/7.3.1.4/src/integrations/forminator/tokens/fr-tokens.php#L136
- https://plugins.trac.wordpress.org/browser/uncanny-automator/tags/7.3.1.4/src/integrations/forminator/triggers/anon-fr-submitform.php#L114
- https://plugins.trac.wordpress.org/changeset?reponame=\u0026old=3607776%40uncanny-automator\u0026new=3607776%40uncanny-automator
- https://www.wordfence.com/threat-intel/vulnerabilities/id/9f2774e8-8b55-4c25-93c3-e0806208b1f3?source=cve