The login_to_simulator method in Linden Lab Second Life, as used by the secondlife:// protocol handler and possibly other Second Life login mechanisms, sends an MD5 hash in cleartext in the passwd field, which allows remote attackers to login to an account by sniffing the network and then sending this hash to a Second Life authentication server.

References

• https://nvd.nist.gov/vuln/detail/CVE-2007-4961
• http://osvdb.org/45947
• http://www.gnucitizen.org/blog/ie-pwns-secondlife