Bugtraq mailing list archives
Re: remote DoS against inetd and ssh
From: super () CE NET (Derek Callaway)
Date: Wed, 8 Sep 1999 11:07:27 -0400
On Fri, 3 Sep 1999, Grzegorz Stelmaszek wrote: <snip>
Both DoS`s use something known as portfuck (e.g. `while true; do telnet host port & done`). 1. If you use it against any inetd service, inetd will shoutdown that service for about 30 minutes (i did not checked, but it seems to be about that time).
Of course this is also true for identd. A cracker doesn't have to be a superuser on a machine in order to disable identd. This makes it considerably more difficult for the administrators of the victim and source hosts to recognize a perpetrator. identd (pidentd, anyway) does not seem to be vulnerable to this when not being wrapped by inetd. I'm not sure if inetd uses fork() to spawn services but if it does, a signal handler should be implemented that restarts services upon receipt of SIGCHLD. <snip>
SOLUTION: propaply running in ulimit envirmont (like qmail does) should help and additionally in inetd remove this strange 'protection'. regards, greg AKA VanitaS *************************************************************************** * Grzegorz Stelmaszek * For my public PGP key: * mailto:greg () tenet pl * finger:greg () tenet pl * http://www.tenet.pl * 18 E9 5E 6D 78 F0 11 F2 ****************************** 45 CF CF 63 77 C0 A4 20
strcpy(hostent->h_name,"jerry.garcia.rocked.com"); Derek Callaway <super () ce net> Programmer -- CE Net, Inc.
Current thread:
- remote DoS against inetd and ssh Grzegorz Stelmaszek (Sep 02)
- Re: remote DoS against inetd and ssh Jedi/Sector One (Sep 08)
- Re: remote DoS against inetd and ssh Derek Callaway (Sep 08)
- Re: remote DoS against inetd and ssh Vincent Janelle (Sep 08)
- <Possible follow-ups>
- Re: remote DoS against inetd and ssh Alexander Boutkhoudze (Sep 07)
- Re: remote DoS against inetd and ssh Jose Nazario (Sep 08)
- Re: remote DoS against inetd and ssh Stas Kisel (Sep 22)