Deserialization of Untrusted Data
In Symfony 2.8.x before 2.8.50 (All 2.x versions in the FrameworkBundle), 3.x before 3.4.26, 4.x before 4.1.12, and 4.2.x before 4.2.7 it is possible to cache objects that may contain bad user input. On serialization or unserialization, this could result in the deletion of files that the current user has access to. This is related to symfony/cache and symfony/phpunit-bridge.
CWE-502 - Deserialization of Untrusted Data
Deserialization of untrusted data vulnerabilities enable an attacker to replace or manipulate a serialized object, replacing it with malicious data. When the object is deserialized at the victim's end the malicious data is able to compromise the victim’s system. The exploit can be devastating, its impact may range from privilege escalation, broken access control, or denial of service attacks to allowing unauthorized access to the application's internal code and logic which can compromise the entire system.