Hackers are actively exploiting a known vulnerability in Sun Microsystems Inc.'s Solaris version of the Unix operating system, security experts said late Monday, urging administrators to check if their system is vulnerable.
The U.S.-government funded Computer Emergency Response Team/Coordination Center (CERT/CC) at Carnegie Mellon University in Pittsburgh said in an advisory that it had received "credible reports" of an exploit for Solaris systems. An exploit is a software tool that can be used to break into computer systems and that is often used by hackers.
The exploit takes advantage of a buffer overflow vulnerability that was first discovered in March 1999. The flaw in a library function used by the CDE (Common Desktop Environment) could allow an attacker to take full control over the system, CERT/CC said. CDE is a graphical user interface that is typically installed by default on Unix systems.
The CDE Subprocess Control Service (dtspcd) is a network daemon that accepts requests from remote clients to execute commands and launch programs remotely. The service does not perform adequate input validation, as a result of which a malicious client could manipulate data sent and cause a buffer overflow, according to CERT/CC.
CERT/CC advises administrators to check if a system is configured to run dtspcd by looking for the entries "dtspc 6112/tcp" in "/etc/services" and "dtspc stream tcp nowait root /usr/dt/bin/dtspcd /usr/dt/bin/dtspcd" in "/etc/inetd.conf".
Many Unix and Linux flavors are vulnerable and many vendors have long issued patches to fix the problem. Any system that does not run dtspcd is not vulnerable to this problem.