Source: cve@mitre.org
Multiple buffer overflows in HP Tru64 UNIX 5.x allow local users to execute arbitrary code via (1) a long -contextDir argument to dtaction, (2) a long -p argument to dtprintinfo, (3) a long -customization argument to dxterm, or (4) a long DISPLAY environment variable to dtterm.
HP Tru64 UNIX 5.x systems are vulnerable to multiple buffer overflow vulnerabilities, allowing local users to execute arbitrary code. Exploitation can occur through several applications, including dtaction, dtprintinfo, dxterm, and dtterm, by providing excessively long arguments or environment variables, potentially leading to complete system compromise.
Step 1: Target Selection: Identify a vulnerable HP Tru64 UNIX 5.x system.
Step 2: Payload Preparation: Craft a malicious payload (e.g., a shellcode) designed to execute commands with elevated privileges.
Step 3: Exploit Delivery (dtaction): Execute dtaction with a long -contextDir argument containing the payload, triggering the buffer overflow.
Step 4: Exploit Delivery (dtprintinfo): Execute dtprintinfo with a long -p argument containing the payload, triggering the buffer overflow.
Step 5: Exploit Delivery (dxterm): Execute dxterm with a long -customization argument containing the payload, triggering the buffer overflow.
Step 6: Exploit Delivery (dtterm): Set the DISPLAY environment variable to a long string containing the payload, then launch dtterm, triggering the buffer overflow.
Step 7: Code Execution: The overflow overwrites memory, including the return address, and redirects program execution to the attacker's payload.
Step 8: Privilege Escalation: The payload executes with the privileges of the user running the vulnerable application, potentially leading to root access.
The vulnerabilities stem from inadequate bounds checking in several HP Tru64 UNIX utilities. Specifically, the affected programs fail to properly validate the size of user-supplied input, such as command-line arguments (-contextDir, -p, -customization) and the DISPLAY environment variable. This allows attackers to craft input that exceeds the allocated buffer size, leading to a buffer overflow. When the attacker-controlled data overwrites critical memory regions (e.g., return addresses, function pointers), it enables the execution of arbitrary code, effectively granting the attacker control over the compromised system. The root cause is a lack of input validation and secure coding practices, failing to account for the potential for malicious input.
Due to the age of the vulnerability, it's unlikely to be directly associated with specific APT groups in recent reports. However, any threat actor targeting legacy systems could leverage this vulnerability. This vulnerability is not listed in the CISA KEV catalog.
Monitor system logs for unusually long arguments passed to dtaction, dtprintinfo, dxterm, and dtterm.
Analyze process execution logs for suspicious activity associated with the vulnerable binaries.
Examine network traffic for unusual patterns related to X11 connections (if exploiting the dtterm vulnerability).
Implement file integrity monitoring to detect changes to system binaries.
Use intrusion detection systems (IDS) with signatures specifically designed to detect buffer overflow attempts against these applications.
Review core dumps for evidence of crashes caused by buffer overflows.
Upgrade to a patched version of HP Tru64 UNIX (if available).
Apply vendor-provided security patches.
Implement input validation to restrict the length and content of arguments passed to the vulnerable applications.
Restrict access to the vulnerable applications to only authorized users.
Disable or remove the vulnerable applications if they are not essential.
Implement a robust system for monitoring and auditing system activity.
Consider using a host-based intrusion detection system (HIDS) to detect and alert on suspicious activity.