Published: February 7, 2017Last modified: February 15, 2024
chroot in GNU coreutils, when used with --userspec, allows local users to escape to the parent session via a crafted TIOCSTI ioctl call, which pushes characters to the terminal's input buffer.
Severity score breakdown
The fix reverted in coreutils http://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=f5d7c0842ef7adc2be6e85f9ef66b35ebbbd6a61, with the following statement: "This reverts commit v8.27-97-g8cb06d4 because the setsid() fallback was not implemented correctly and disabling the ioctl was not a complete solution to the security issue of the child being passed the tty of the parent. Given runcon is not really a sandbox command, the advice is to use `runcon ... setsid ...` to avoid this particular issue."
|Will not fix (9.1-r0)