Apache.NMS.ActiveMQ clients can be forced to allocate excessively large memory blocks or crash when an attacker sends a specially crafted OpenWire frame containing an oversized or negative length. The unvalidated frame size and length fields bypass built‑in safeguards, resulting in OutOfMemoryException events or uncaught exceptions that terminate the client process. The weakness is a classic instance of unchecked recursion or unbounded memory consumption (CWE-789).

The vulnerability affects all users of the Apache.NMS.ActiveMQ .NET OpenWire client library distributed before version 2.3.0. The CNA lists the Apache Software Foundation:Apache ActiveMQ NMS OpenWire Client Library as the affected product.

Because the attack vector relies on manipulating frames in an unencrypted or compromised broker connection, the exploitation likelihood depends on network exposure and encryption use. No EPSS score is available and the vulnerability is not listed in CISA's KEV catalog, but the absence of frame validation means that any client with network access to a broker can be targeted. The impact is a denial of service to the client application, which could affect multiple users if the client runs in a shared environment.