Laravel MagicLink creates links for authentication without a password or for accessing private content. From 2.0.0 until 2.25.1, MagicLink stores serialized action objects in the magic_links.action database column and deserializes them through src/MagicLink.php and src/Actions/ResponseAction.php without sufficient integrity protection, while an unsafe legacy unserialize() fallback remains reachable. An attacker who can manipulate database records, such as through a separate SQL injection or compromised administrative access, can insert a malicious serialized object graph containing executable closure behavior; visiting the associated magic link then deserializes the record and can execute arbitrary code in the application process. The affected path is restricted to manipulated action records and does not independently provide database-write access. This issue is fixed in version 2.25.1.

Affected: Packagist: cesargb/laravel-magiclink

## Description

MagicLink stores serialized action objects in the `magic_links.action` database column and deserializes them without integrity validation or class allowlisting in [src/MagicLink.php](src/MagicLink.php#L59-L77) and [src/Actions/ResponseAction.php](src/Actions/ResponseAction.php#L64-L77). An attacker with the ability to manipulate database records (e.g., via SQL injection or compromised admin access) could inject malicious serialized objects containing arbitrary closures, leading to Remote Code Execution (RCE) when the magic link is visited.

## Resolution

The vulnerability has been mitigated through HMAC-signed serialization using the application key, class allowlisting restricted to `ActionAbstract` subclasses and framework classes, strict type validation preventing arbitrary object storage, and backward compatibility support for legacy data via `allowed_classes` in `unserialize()`. Implementation includes a new [Serializable](src/Security/Serializable/Serializable.php) security class with signing/verification, refactored getter/setter methods in MagicLink.