FreeBSD Resources
Mailing lists pertaining to FreeBSD. freebsd-security and freebsd-security-notifications are sources of official FreeBSD specific notifications.
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/eresources.html

CyberCrime-Alerts
Computer crimes and related arrests are the focus of these mail alerts. Subscribers can receive 5-20 messages per week as news breaks.
http://topica.com/lists/cybercrime-alerts/

IWS INFOCON Mailing List
The INFOCON mailing list is devoted to the discussion of cyberthreats and all aspects of information operations, including offensive and defensive information warfare, information assurance, psychological operations, electronic warfare, ....
http://www.iwar.org.uk/general/mailinglist.htm

SecureMac
Macintosh security mailing list for advisories, patches, and alerts.
http://www.securemac.com/

Bugtraq Moderated by Security Focus
Bugtraq mailing list archives of UNIX, NT, Win95, Novell, and Mac, bugs and exploits.
http://online.securityfocus.com/archive

Redhat Linux Mailing list manager
Focuses on Linux and Redhat related security information specifically the Linux-security and Redhat-watch-list lists.
https://listman.redhat.com/mailman/listinfo/

Microsoft TechNet Security - Product Security Notification
Microsoft techNet Security - Product Security Notification. Instructions on how to join the mailing list for Product Security bulletins notification.
http://www.microsoft.com/technet/security/bulletin/notify.asp

Debian GNU/Linux -- Mailing List Subscription
Security mailing lists that deal with Debian Linux security issues, specifically the debian-security-announce and debian-security lists.
http://www.debian.org/MailingLists/subscribe

Moderated Firewall and Security Mailing List
Firewall-wizards is a high-quality fully moderated firewall and security mailing list.
http://honor.icsalabs.com/mailman/listinfo/firewall-wizards

The 'Security Digest' Archives
Dedicated to the history of the early 'Security Digest' archives, from the Unix 'Security Mailing List', through the Zardoz 'Security Digest' to the Core 'Security List'.
http://securitydigest.org/

Alert Security Mailing List
Monthly security tips and alert mailing list. Pay subscription service provides information, tips and developments to protect your Internet computer security
http://www.w3.easynet.co.uk/unitel/services/alert.html

Der Keiler
Searchable real-time updated archive of major security lists and newsgroups, including Cert, Securiteam, Linuxsecurity, VulnWatch, Full-Disclosure, Bugtraq, Incidents, Securityfocus, and several Usenet groups.
http://www.derkeiler.com

Security Clipper
Mailing list aggregator offering a selection of security lists to monitor.
http://www.securityclipper.com/

SecLists.org
Website run by Fyodor of the NMAP project, a collection of security lists.
http://www.seclists.org

SecuriTeam Mailing Lists
Location of various security mailing lists pertaining to exploits, hacking tools, and others.
http://www.securiteam.com/mailinglist.html

Computer Forensics Training Mailing List
Computer Forensics and incident response mailing list
http://www.infosecinstitute.com/courses/computer_forensics_training.html

SCADA Security List
Mailing list concerning DCS and SCADA Security
http://www.infosecinstitute.com/courses/scada_security_training.html

SGI and IRIX security list
List for SGI and IRIX security
http://lists.man.ac.uk/mailman/listinfo/sg-users

Training Reviews List
Security training reviews, daily updates via newsletter available.
http://www.trainingreviews.com/Security/index.html

InfoSec News
Privately-run medium traffic list that caters to distribution of information security news articles.
http://www.infosecnews.org/

ISO17799 & ISO27001 News
News, background and updates on these international security standards.
http://www.molemag.net/