openEQUELLA before 2026.1.0 contains an authenticated remote code execution vulnerability that allows any authenticated non-guest user to execute arbitrary code by exploiting Java deserialization in the HTTP invoker endpoint at /invoker/*. Attackers can bypass the class-name denylist enforced by PluginAwareObjectInputStream by nesting a serialized payload inside a java.security.SignedObject, causing the inner stream to be deserialized by a separate ObjectInputStream that does not apply the denylist, ultimately reaching a JNDI sink and enabling code execution.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
Low
Basic privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0