I like excitement in my life. I go on roller coasters, I ride my bike without a helmet, I make risky financial decisions. I treat my servers no differently. When my Linux vendor releases security updates, I think: I could apply these patches, but why would I? If I did, I'd have to coordinate with my users to schedule a maintenance window for 2am on a Sunday and babysit those systems while they reboot, which is seriously annoying, hurts our availability, and interrupts my beauty sleep (and trust me, I need my beauty sleep). Plus, where's the fun in having a fully-patched system? Without open vulnerabilities, how else would I have won a ton of money in my office's Vulnerability Bingo games?
How can I get in on some Vulnerability Bingo action, you ask? Simple: get yourself some bingo cards, be sure not to patch your systems, and place chips on appropriate squares when your machines are compromised. Or, as a fun variant, place chips when your friends' machines get compromised! For the less adventurous, place chips as relevant Common Vulnerabilities and Exposures are announced.
What's really great is the diversity of vulnerabilities. In 2009 alone, Vulnerability Bingo featured:
physically proximate denial of service attacks (CVE-2009-1046).
local denial of service attacks (CVE-2009-0322, CVE-2009-0031, CVE-2009-0269, CVE-2009-1242, CVE-2009-2406, CVE-2009-2407, CVE-2009-2287, CVE-2009-2692, CVE-2009-2909, CVE-2009-2908, CVE-2009-3290, CVE-2009-3547, CVE-2009-3621, CVE-2009-3620) coming in at least 5 great flavors: faults, memory corruption, system crashes, hangs, and the kernel OOPS!
And the perennial favorite, remote denial of service attacks (CVE-2009-1439, CVE-2009-1633, CVE-2009-3613, CVE-2009-2903) including but not limited to system crashes, IOMMU space exhaustion, and memory consumption!
How about leaking potentially sensitive information from kernel memory (CVE-2009-0676, CVE-2009-3002, CVE-2009-3612, CVE-2009-3228) and remote access to potentially sensitive information from kernel memory (CVE-2009-1265)?
Perhaps I can interest you in some privilege escalation (CVE-2009-2406, CVE-2009-2407, CVE-2009-2692, CVE-2009-3547, CVE-2009-3620), or my personal favorites, arbitrary code execution (CVE-2009-2908) and unknown impact (CVE-2009-0065, CVE-2009-1633, CVE-2009-3638).
Sometimes you get a triple threat like CVE-2009-1895, which "makes it easier for local users to leverage the details of memory usage to (1) conduct NULL pointer dereference attacks, (2) bypass the mmap_min_addr protection mechanism, or (3) defeat address space layout randomization (ASLR)". Three great tastes that taste great together -- and a great multi-play Bingo opportunity!