CVE-2019-9146 in Jamf Self Service
Summary
by MITRE
Jamf Self Service 10.9.0 allows man-in-the-middle attackers to obtain a root shell by leveraging the "publish Bash shell scripts" feature to insert "/Applications/Utilities/Terminal app/Contents/MacOS/Terminal" into the TCP data stream.
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Analysis
by VulDB Data Team • 07/19/2023
The vulnerability identified as CVE-2019-9146 represents a critical security flaw in Jamf Self Service version 10.9.0 that enables man-in-the-middle attacks to escalate privileges to root access. This vulnerability specifically targets the "publish Bash shell scripts" functionality within the software, creating an avenue for attackers to inject malicious commands into the system's TCP data stream. The flaw exploits the trust relationship between the application and its network communications, allowing unauthorized parties to manipulate the execution flow of shell scripts through carefully crafted network traffic interception.
The technical implementation of this vulnerability leverages the Terminal application's binary path within the macOS environment to execute malicious commands with elevated privileges. When Jamf Self Service processes bash scripts through its publish feature, the application fails to properly validate or secure the network communication channel, enabling attackers to insert their own commands into the data stream. The specific path "/Applications/Utilities/Terminal.app/Contents/MacOS/Terminal" becomes a critical injection point where attacker-controlled code can be executed with root privileges, effectively bypassing normal user permission controls. This represents a classic case of insecure network communication handling that violates fundamental security principles of input validation and privilege separation.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it provides attackers with complete control over affected systems. Once a root shell is obtained through this method, adversaries can execute arbitrary commands, modify system files, install persistent backdoors, and access sensitive data without detection. The vulnerability affects organizations that rely on Jamf Self Service for managing macOS devices, potentially compromising entire enterprise networks where these systems are deployed. The man-in-the-middle attack vector suggests that the vulnerability could be exploited in corporate networks where traffic interception is possible, making it particularly dangerous in environments with insufficient network security controls.
Organizations should implement immediate mitigations including network segmentation to prevent unauthorized access to Jamf Self Service communication channels, deployment of network monitoring tools to detect unusual TCP stream modifications, and application whitelisting policies to restrict execution of unauthorized binaries. The vulnerability aligns with CWE-310, which addresses cryptographic weaknesses in network communications, and maps to ATT&CK technique T1059.004 for command and scripting interpreter usage. Security teams must also ensure that Jamf Self Service is updated to versions that address this vulnerability, while implementing comprehensive network security controls including SSL/TLS inspection and proper certificate validation to prevent similar man-in-the-middle attacks across the organization's infrastructure.