Queuejumper

QueueJumper, designated as CVE-2023-21554, is a critical vulnerability discovered in the Microsoft Message Queuing (MSMQ) service. It is a remote code execution flaw that could allow unauthenticated attackers to remotely execute arbitrary code within the Windows service process mqsvc.exe. This vulnerability has been given a CVSS score of 9.8 and received Microsoft's highest exploitability rating, indicating its severity and potential impact. The vulnerability was dubbed QueueJumper due to its ability to bypass normal processing queues and execute malicious code. The vulnerability lies in the offset of an allocated buffer to out-of-bounds write, which can be manipulated using attacker-controlled data. In-depth technical analysis revealed that the remote exploitation of QueueJumper, while not impossible, is challenging due to certain requirements. Despite these challenges, successful exploitation would result in unauthorized access and control over affected systems, posing a significant risk to system integrity and confidentiality. In response to the discovery of QueueJumper, Check Point IPS developed and deployed a signature named “Microsoft Message Queuing Remote Code Execution (CVE-2023-21554)” to detect and protect their customers against this vulnerability. While the potential for remote exploitation exists, the complexity involved makes it difficult to accomplish. However, organizations are strongly advised to apply the necessary patches and updates to mitigate the risk associated with this vulnerability.