*** This bug is a security vulnerability *** Public security bug reported:
Tested in Ubuntu 12.04 and 13.04. The --user, -u, or /etc/default/tftpd-hpa TFTP_USERNAME="tftp" options are ignored when running the tftpd-hpa service. I pulled the source with wget https://www.kernel.org/pub/software/network/tftp/tftp-hpa/tftp- hpa-5.2.tar.xz and compiled. Ran with /root/tftp-hpa-5.2/tftpd/tftpd --listen -u nobody --address 0.0.0.0:69 --secure /var Result was root@ubuntu:/var/log# ps -ef | grep tftpd root 7955 1 0 13:55 ? 00:00:00 /root/tftp-hpa-5.2/tftpd/tftpd --listen -u nobody --address 0.0.0.0:69 --secure /var I expected the process uid to be that of "nobody". Killing the process and trying again I also looked at /proc to see what it thought about it: root@ubuntu:/var/log# cat /proc/8037/task/8037/status Name: tftpd State: S (sleeping) Tgid: 8037 Pid: 8037 PPid: 1 TracerPid: 0 Uid: 0 0 0 0 Gid: 0 0 0 0 FDSize: 64 Groups: 0 VmPeak: 13048 kB VmSize: 13048 kB VmLck: 0 kB VmPin: 0 kB VmHWM: 140 kB VmRSS: 140 kB VmData: 444 kB VmStk: 136 kB VmExe: 32 kB VmLib: 2140 kB VmPTE: 44 kB VmSwap: 0 kB Threads: 1 SigQ: 0/31432 SigPnd: 0000000000000000 ShdPnd: 0000000000000000 SigBlk: 0000000000000000 SigIgn: 0000000000010000 SigCgt: 0000000000004003 CapInh: 0000000000000000 CapPrm: 0000001fffffffff CapEff: 0000001fffffffff CapBnd: 0000001fffffffff Seccomp: 0 Cpus_allowed: ffffffff,ffffffff Cpus_allowed_list: 0-63 Mems_allowed: 00000000,00000001 Mems_allowed_list: 0 voluntary_ctxt_switches: 1 nonvoluntary_ctxt_switches: 0 ** Affects: tftp-hpa (Ubuntu) Importance: Undecided Status: New ** Tags: tftp ** Information type changed from Private Security to Public Security -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1188827 Title: User option (-u or --user) is ignored To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/tftp-hpa/+bug/1188827/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs