Security Basics mailing list archives
RE: Verifying E-Mail Addresses
From: "Krpata, Tyler" <tkrpata () bjs com>
Date: Tue, 24 Oct 2006 18:03:45 -0400
The SMTP VRFY command is supposed to do this, but most mail servers disable it due to privacy concerns. There's no other reliable way to do it. In theory you might be able to write something custom that goes to the mail server and does a "mail from/rcpt to" and checks the response, but that may be unreliable and could potentially be frowned upon by the ISP. -----Original Message----- From: Mister Dookie [mailto:misterdookie () gmail com] Sent: Tuesday, October 24, 2006 5:03 PM To: security-basics () securityfocus com Subject: Verifying E-Mail Addresses Hello list, Is there a way to verify that an e-mail address (e.g."johnsmith () company com") is valid and exists or does not exist (is a fake e-mail address) without actually sending a message to that address and awaiting the response? Here's why this is a security issue. Our company administers a small "municipal-type" 802.11 network where for limited open-access the only form of ID we require is an e-mail address and a password. We simple don't have the resources to send out e-mails and then have verification and so forth. We are trying to prevent users from entering fake addresses into our system. We want at least a small amount of accountability. We would like to be able to do a quick check, say query an IMAP, POP3, or SMTP and check to see if there is actually an account at that address without sending a verification e-mail and waiting for users to click on a link or get something that bounces back. Does something like that exist? I do recognize that somebody can enter a valid e-mail address that does not belong to them, but we are trying to address one issue at a time. At this point we are just trying to prevent people who give us "dude () dude com" from getting on to our network. Thanks, John ------------------------------------------------------------------------ --- This list is sponsored by: Norwich University EARN A MASTER OF SCIENCE IN INFORMATION ASSURANCE - ONLINE The NSA has designated Norwich University a center of Academic Excellence in Information Security. Our program offers unparalleled Infosec management education and the case study affords you unmatched consulting experience. Using interactive e-Learning technology, you can earn this esteemed degree, without disrupting your career or home life. http://www.msia.norwich.edu/secfocus ------------------------------------------------------------------------ --- --------------------------------------------------------------------------- This list is sponsored by: Norwich University EARN A MASTER OF SCIENCE IN INFORMATION ASSURANCE - ONLINE The NSA has designated Norwich University a center of Academic Excellence in Information Security. Our program offers unparalleled Infosec management education and the case study affords you unmatched consulting experience. Using interactive e-Learning technology, you can earn this esteemed degree, without disrupting your career or home life. http://www.msia.norwich.edu/secfocus ---------------------------------------------------------------------------
Current thread:
- Re: Verifying E-Mail Addresses, (continued)
- Re: Verifying E-Mail Addresses Saqib Ali (Oct 25)
- Re: Verifying E-Mail Addresses MaddHatter (Oct 25)
- RE: Verifying E-Mail Addresses Roger A. Grimes (Oct 25)
- Re: Verifying E-Mail Addresses Kurtis Miller (Oct 25)
- Re: Verifying E-Mail Addresses nick (Oct 25)
- Re: Verifying E-Mail Addresses Ansgar -59cobalt- Wiechers (Oct 25)
- Re: Verifying E-Mail Addresses Dave Ockwell-Jenner (Oct 25)
- Re: Verifying E-Mail Addresses Robert Inder (Oct 27)
- Re: Verifying E-Mail Addresses Roman Shirokov (Oct 27)
- Re: Verifying E-Mail Addresses Matt Lye (Oct 27)
- RE: Verifying E-Mail Addresses Krpata, Tyler (Oct 25)
- RE: Verifying E-Mail Addresses Jimmie Jones (Oct 25)
- RE: Verifying E-Mail Addresses Weir, Jason (Oct 25)
- Re: Verifying E-Mail Addresses kenneth_z (Oct 25)
- RE: Verifying E-Mail Addresses Oyesanya, Femi (Oct 25)
- Re: Verifying E-Mail Addresses bucklerk (Oct 25)
- Re: Verifying E-Mail Addresses Ansgar -59cobalt- Wiechers (Oct 25)