*** This bug is a security vulnerability *** Public security bug reported:
Type this at a shell prompt in gnome-terminal: $ (yes&) y y y y y y ... Denial of service. Shell becomes totally unresponsive. Subshell command is uninterruptible. An old one that affects bash, dash, ksh, tcsh, and zsh shells at least in all versions in Ubuntu and further back in Ubuntu pre-history too. Please note the issue is not related to https://wiki.ubuntu.com/SecurityTeam/Policies#Unlimited_Local_Resource_Utilization $ (yes &) is not a fork bomb or any other kind of resource overutilization. There is only one subshell and only one subprocess being executed in it. The issue is with buggy signal handling. ** Affects: bash (Ubuntu) Importance: Undecided Status: New ** Affects: dash (Ubuntu) Importance: Undecided Status: New ** Affects: ksh (Ubuntu) Importance: Undecided Status: New ** Affects: tcsh (Ubuntu) Importance: Undecided Status: New ** Affects: zsh (Ubuntu) Importance: Undecided Status: New ** Information type changed from Private Security to Public Security ** Also affects: gnubash Importance: Undecided Status: New ** Project changed: gnubash => ubuntu ** Package changed: ubuntu => bash (Ubuntu) ** Also affects: zsh Importance: Undecided Status: New ** Project changed: zsh => zsh (Ubuntu) ** Also affects: dash Importance: Undecided Status: New ** Project changed: dash => dash (Ubuntu) ** Also affects: mksh Importance: Undecided Status: New ** Project changed: mksh => ksh (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1213743 Title: subshell that instantly locks up bash, dash, ksh, tcsh, and zsh To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/bash/+bug/1213743/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
