CVE-2017-7504 in JBoss Application Server
Summary
by MITRE
HTTPServerILServlet.java in JMS over HTTP Invocation Layer of the JbossMQ implementation, which is enabled by default in Red Hat Jboss Application Server <= Jboss 4.X does not restrict the classes for which it performs deserialization, which allows remote attackers to execute arbitrary code via crafted serialized data.
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Analysis
by VulDB Data Team • 12/25/2020
The vulnerability identified as CVE-2017-7504 represents a critical deserialization flaw within the JBossMQ implementation of the JBoss Application Server version 4.x and earlier. This vulnerability exists in the HTTPServerILServlet.java component which handles JMS over HTTP invocation layer communications. The flaw stems from the absence of proper class restriction mechanisms during the deserialization process, allowing remote attackers to craft malicious serialized data that can be executed on the target system. The vulnerability is particularly concerning because JBossMQ is enabled by default in these older versions, making systems inherently vulnerable without additional configuration changes.
The technical implementation of this vulnerability resides in the HTTPServerILServlet.java file where the deserialization process lacks proper validation of the serialized data's class types. When the servlet receives serialized data through HTTP requests, it performs deserialization without verifying whether the target classes are permitted or safe for execution. This behavior creates an attack surface where attackers can leverage Java deserialization vulnerabilities to execute arbitrary code on the server. The flaw aligns with CWE-502 which specifically addresses deserialization of untrusted data, and represents a classic example of insecure deserialization that has been exploited in numerous high-profile attacks. The vulnerability essentially allows attackers to bypass normal security controls by injecting malicious serialized objects that execute code with the privileges of the running application server.
The operational impact of CVE-2017-7504 is severe and potentially catastrophic for affected organizations. Remote code execution capabilities enable attackers to gain complete control over the vulnerable JBoss application server, potentially leading to data breaches, service disruption, and further lateral movement within the network. Attackers can leverage this vulnerability to install backdoors, exfiltrate sensitive data, or use the compromised server as a launching point for attacks against other systems. The default enablement of JBossMQ in these versions means that organizations are exposed by default without requiring additional configuration steps, significantly increasing the attack surface and attack probability. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under the T1059.007 technique for command and script interpreter, specifically targeting the Java deserialization attack vector.
Mitigation strategies for CVE-2017-7504 require immediate action from affected organizations to address the root cause of the vulnerability. The primary recommendation involves upgrading to a supported version of JBoss Application Server where JBossMQ has been properly secured or disabled by default. Organizations should also implement network segmentation and firewall rules to restrict access to the JMS over HTTP invocation layer ports, reducing the attack surface. Additionally, implementing proper input validation and class restriction mechanisms in the deserialization process can provide defense-in-depth measures. Security monitoring should be enhanced to detect unusual deserialization activities and potential exploitation attempts. The vulnerability also highlights the importance of following secure coding practices and adhering to the principle of least privilege in application server configurations to minimize the potential impact of similar vulnerabilities in the future.