Security Basics mailing list archives
RE: Which ports to block?
From: "Ed Spencer" <espencer () usa net>
Date: Mon, 26 Jul 2004 11:42:42 -0800
It's safest to block thru 65535. There are many services that run above 1023 and these would be allowed through the firewall if you don't block them (depending on the firewall and implementation). Remember just because they're not 'well-known' doesn't mean that they're not well-known. ;-) Ed Spencer MCSE/MCT/MCP/CNA/A+/Network+/Security+ Network Administrator Aramark Corporation Denali National Park. -----Original Message----- From: Ferino Mardo [mailto:RMardo () ALJOMAIHBEV com] Sent: Saturday, July 24, 2004 12:04 AM To: security-basics () securityfocus com Subject: Which ports to block? In setting up a "deny all" rule from a firewall, is it safe to block ports 0 to 65535 or only up to 1023? My interest are only to allow port 53 udp, 25, and 80. ------------------------------------------------------------------------ --- Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off any course! All of our class sizes are guaranteed to be 10 students or less to facilitate one-on-one interaction with one of our expert instructors. Attend a course taught by an expert instructor with years of in-the-field pen testing experience in our state of the art hacking lab. Master the skills of an Ethical Hacker to better assess the security of your organization. Visit us at: http://www.infosecinstitute.com/courses/ethical_hacking_training.html ------------------------------------------------------------------------ ---- --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.726 / Virus Database: 481 - Release Date: 7/22/2004 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.726 / Virus Database: 481 - Release Date: 7/22/2004 --------------------------------------------------------------------------- Ethical Hacking at the InfoSec Institute. Mention this ad and get $545 off any course! All of our class sizes are guaranteed to be 10 students or less to facilitate one-on-one interaction with one of our expert instructors. Attend a course taught by an expert instructor with years of in-the-field pen testing experience in our state of the art hacking lab. Master the skills of an Ethical Hacker to better assess the security of your organization. Visit us at: http://www.infosecinstitute.com/courses/ethical_hacking_training.html ----------------------------------------------------------------------------
Current thread:
- Which ports to block? Ferino Mardo (Jul 26)
- Re: Which ports to block? mike (Jul 26)
- RE: Which ports to block? Ed Spencer (Jul 26)
- Re: Which ports to block? steve (Jul 26)
- Re: Which ports to block? VHP3 (Jul 27)
- <Possible follow-ups>
- RE: Which ports to block? Barber, Chris Mr. ATEC/Contractor (Jul 26)
- RE: Which ports to block? Hamish Stanaway (Jul 27)
- RE: Which ports to block? Ferino Mardo (Jul 27)
- RE: Which ports to block? Majed Mohammed Ayoub Al-Shodari (Jul 27)