A flaw was recently discovered in the ptrace syscall function of Linux kernel 2.6, 3.2, and 3.13, affecting only x86_64 processors. This could be easily exploited by an attacker, which could cause a DoS (Denial of Service) attack or gain root privileges. The security flaw was discovered by Andy Lutomirski and can be easily fixed by upgrading your Ubuntu 14.04 LTS system(s) to the linux-image-3.13.0-30 (3.13.0-30.55) package(s), Ubuntu 12.04 LTS to the linux-image-3.2.0-65 (3.2.0-65.99) package(s), and Ubuntu 10.04 LTS to the linux-image-2.6.32-62 (2.6.32-62.126) package(s).