If you run a 64-bit version of Linux, take note, your system may be vulnerable to attack. Red Hat recently announced an exploit that would allow a local, unprivileged user to escalate their privileges, and while there are published workarounds, they may not completely plug up the security hole.
"The published workarounds that we've seen, including the workaround recommended by Red Hat, can themselves be worked around by an attack to still exploit the system," Jeff Arnold, CEO of Ksplice, said in a blog post . "For now, to be responsible and avoid helping attackers, we don't want to provide those technical details publicly; we've contacted Red Hat and other vendors with the details and we'll cover them in a future blog post, in a few weeks."
In the mean time, Ksplice -- which isn't a free service, but does offer a free trial -- can be used to receive advance notice of upcoming patches.
"Although it might seem self-serving, I do know of one sure way to fix this vulnerability right away on running production systems, and it doesn’t even require you to reboot: you can (for free) download Ksplice Uptrack and fully update any of the distributions that we support (We support RHEL, CentOS, Debian, Ubuntu, Parallels Virtuozzo Containers, OpenVZ, and CloudLinux," Arnold explains. "For high profile updates like this one, Ksplice optionally makes available an update for your distribution before your distribution officially releases a new kernel). We provide a free 30-day trial of Ksplice Uptrack on our website, and you can use this free trial to protect your systems, even if you cannot arrange to reboot anytime soon. It’s the best that we can do to help in this situation, and I hope that it’s useful to you."
Keep in mind that if an attacker has already comprised one of your Linux rigs, updating the system won't do a lick of good by itself since the exploit installs a backdoor. You can use this test tool to find out for sure.