Solaris 10 UFS File System Has Denial of Service Vulnerability

Published: November 9, 2006

by Timothy Prickett Morgan

Secunia, which tracks security vulnerabilities in operating systems and other software, reported this week that it has received a report that the Solaris 10 Unix variant from Sun Microsystems has a denial of service security vulnerability in the UFS file system.

According to the Secunia report, the vulnerability would allow "malicious, local users to cause a DoS (Denial of Service)." The report went on to say that the vulnerability "is caused due to an improper handling of corrupted data structures in the UFS file system. This can be exploited to crash the system or corrupt the file system by mounting a specially crafted file system image." The security company warns that earlier versions of Solaris could be affected, and that end users should not mount untrusted file systems.

The security vulnerability exists because of a flaw in the way the UFS file system reacts when it is given corrupted data structures. As with many other vulnerabilities, you can cause a machine to puke all over itself and knock it offline if you know how to make it sick. (To speak metaphorically, not technically.) This vulnerability has been given a "not critical" status, since it can only be locally exploited, and has not been patched yet by Sun.