Bugtraq mailing list archives
Mail relay vulnerability in RedHat 5.0, 5.1, 5.2
From: luyer () UCS UWA EDU AU (David Luyer)
Date: Fri, 16 Jul 1999 18:12:54 +0800
We have recently found ourself used as mail relays and put into the ORBS mail relay blocking system due to a bug in early anti-relay rulesets as used in both our local rules and RedHat 5.0, 5.1 and 5.2 (even though we never touch RedHat on serious servers, somehow our home-brew rulesets ended up bug-compatible). It seems that some spammers out there have discovered the power of: RCPT TO: <"target () destination com"@relay.host.name> where relay.host.name is obtained by reverse DNS lookup. Users of sendmail 8.9.x of course have no problem, neither do those who have updated their mail relay prevention rulesets recently, but I think there are enough RedHat 5.0, 5.1 and 5.2 users who are unaware of the problem to make it worth sending this out. I have put out a quick little script which fixes this. The script can be found at: ftp://typhaon.ucs.uwa.edu.au/pub/strobe-classb/RH5.0-5.2-patchscript This problem is checked for by my latest relay scanner at: ftp://typhaon.ucs.uwa.edu.au/pub/strobe-classb/strobe-classb-v1.8.tgz (some additional information about open relays and some problems they present can be found at http://typhaon.ucs.uwa.edu.au/presentations.html under 'E-mail Security', but hopefully everyone is well-informed of the issues by now; that paper is quite dated even if it is under a year old) David.
Current thread:
- Re: Shared memory DoS's (Redhat retraction), (continued)
- Re: Shared memory DoS's (Redhat retraction) Mike Perry (Jul 15)
- Re: Shared memory DoS's (Redhat retraction) Jim Dennis (Jul 19)
- Linux +ipchains+ ping -R Andrej Todosic (Jul 22)
- Re: Linux +ipchains+ ping -R Scott (Jul 23)
- Update to Microsoft Security Bulletin (MS99-025) aleph1 () UNDERGROUND ORG (Jul 23)
- Re: Shared memory DoS's (Redhat retraction) Wietse Venema (Jul 22)
- Alert: RDS IIS vulnerability/fix .rain.forest.puppy. (Jul 23)
- Re: Shared memory DoS's Dick St.Peters (Jul 15)
- Re: Shared memory DoS's Nicolas V. Chernyy (Jul 15)
- Re: Shared memory DoS's Mike Perry (Jul 17)
- Mail relay vulnerability in RedHat 5.0, 5.1, 5.2 David Luyer (Jul 16)
- Re: Mail relay vulnerability in RedHat 5.0, 5.1, 5.2 Ollivier Robert (Jul 19)
- Re: Mail relay vulnerability in RedHat 5.0, 5.1, 5.2 Matt Dunn (Jul 22)
- Re: Mail relay vulnerability in RedHat 5.0, 5.1, 5.2 Daniele Orlandi (Jul 24)
- Re: Shared memory DoS's Glynn Clements (Jul 16)
- Re: Shared memory DoS's Mike Perry (Jul 16)
- Re: Shared memory DoS's Howard Kaye (Jul 19)
- Samba 2.0.5 security fixes Andrew Tridgell (Jul 20)
- Re: Shared memory DoS's Richard Shetron (Jul 20)
- Delegate creates directories writable for anyone Olaf Seibert (Jul 21)
- Administrivia Aleph One (Jul 22)
(Thread continues...)
- Re: Shared memory DoS's (Redhat retraction) Mike Perry (Jul 15)