Docker 1.12.6 Fixes Privilege Escalation Vulnerability
From the 'Great Container Escape' files:
The Docker Engine 1.12.6 release debuted on Jan. 10 as a security update for all Docker container users. The new engine fixes single flaw identified as CVE-2016-9962, title, 'Insecure opening of file-descriptor allows privilege escalation.'
According to the bug report:
RunC allowed additional container processes via `runc exec` to be ptraced by the pid 1 of the container. This allows the main processes of the container, if running as root, to gain access to file-descriptors of these new processes during the initialization and can lead to container escapes or modification of runC state before the process is fully placed inside the container.
Umm K. That's not good. A core promise of Docker Engine and container usage overall is container isolation, though the risk of an 'escape' is not to be taken lightly.
It's great to see Docker move quickly to patch security issues like this. Let's hope that users, patch quickly too, before Proof of Concept exploit code shows up in the wild (or worse - in Metasploit so script kiddies can point/click escape..).
Sean Michael Kerner is a senior editor at InternetNews.com. Follow him on Twitter @TechJournalist.