Source: cve@mitre.org
Vulnerability in integer multiplication emulation code on SPARC architectures for SunOS 4.1 through 4.1.2 allows local users to gain root access or cause a denial of service (crash).
Critical vulnerability in the integer multiplication emulation code on older SunOS systems allows for local privilege escalation to root, granting attackers complete control. This vulnerability, dating back to the early 1990s, presents a significant risk to any legacy systems still in operation, potentially leading to system compromise or denial of service.
Step 1: Trigger the Vulnerability: A local user executes a specially crafted program designed to trigger the integer overflow within the multiplication emulation code. This program provides specific input values to a multiplication operation that will cause an overflow.
Step 2: Overflow Condition: The multiplication operation, due to the lack of proper bounds checking, overflows, resulting in an incorrect result.
Step 3: Memory Corruption: The incorrect result from the overflow is then used to overwrite critical memory locations. This could involve overwriting the process's UID and GID to 0 (root).
Step 4: Privilege Escalation: By manipulating the UID and GID, the attacker's process now operates with root privileges.
Step 5: Command Execution: The attacker can now execute commands with root privileges, gaining full control of the system.
The vulnerability stems from a flaw in the integer multiplication emulation code within the SPARC architecture implementation of SunOS 4.1 through 4.1.2. Specifically, the code fails to properly handle integer overflow conditions during multiplication. This leads to a predictable outcome that can be leveraged to overwrite critical memory locations. The root cause is a lack of bounds checking or proper error handling when performing multiplication operations, allowing crafted inputs to cause an integer overflow. This overflow can then be exploited to overwrite sensitive data, such as the process's user ID (UID) and group ID (GID), effectively granting the attacker root privileges. The specific function responsible for the vulnerability is likely within the kernel's math library or related system calls that handle integer arithmetic. The lack of modern security features, such as address space layout randomization (ASLR) and data execution prevention (DEP), further exacerbates the exploitability of this vulnerability.
Due to the age of the vulnerability, it's unlikely to be actively targeted by sophisticated APTs. However, any attacker with basic knowledge could exploit this. This vulnerability is not listed in the CISA KEV catalog due to its age and the rarity of affected systems.
Monitor system logs for unusual process behavior, especially processes attempting to change their UID/GID.
Analyze core dumps for signs of memory corruption or unexpected values in critical process structures.
Network traffic analysis is unlikely to reveal exploitation, as it's a local privilege escalation.
Use file integrity monitoring tools to detect changes to system binaries or configuration files.
Check for the presence of known exploit files or scripts on the system.
The primary remediation is to immediately upgrade to a supported operating system. This is the most crucial step.
If upgrading is not possible, apply any available security patches for SunOS 4.1.x. However, patches may be difficult to find.
Implement strict access controls, limiting user privileges to the minimum necessary.
Regularly audit system logs for suspicious activity.
Consider isolating vulnerable systems on a separate network segment to limit potential damage.
Implement intrusion detection and prevention systems (IDS/IPS) to monitor for malicious activity.