Free public sources of malicious URLs

The following sites aim to provide public links to malicious URLs for free to security professionals and enthusiasts. Naturally we advise caution when opening any of the URLs listed there, although not all are necessarily suitable for e.g. testing anti-malware products (as some of those URLs appear to be PUA, extinct, non-working, etc., but some AVs tend to block such sites anyway as they know that some users may use them for testing). The few ones below are the most known free resources and among the better ones.

hxxp://www.malwaredomainlist.com/
hxxp://support.clean-mx.de/clean-mx/viruses.php
hxxp://malc0de.com/database/
hxxp://www.virussign.com/index.html
hxxp://vxvault.net//ViriList.php
hxxp://malshare.com/
hxxp://cybercrime-tracker.net/