<A HREF="http://news.zdnet.com/2100-1009_22-6158955.html?tag=nl.e589">Solaris 10 is at risk of a zero-day exploit,</A> due to security bugs in its telnet service, Sun Microsystems warned Tuesday. The "highly critical" vulnerabilities could enable attackers to gain unauthorized access to a user's system without requiring the user to download exploit code, said Johannes Ullrich, chief research officer at the Sans Institute, which also issued a security advisory.