The Remote Installation Service (RIS) in Microsoft Windows 2000 SP4 uses a TFTP server that allows anonymous access, which allows remote attackers to upload and overwrite arbitrary files to gain privileges on systems that use RIS.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A375
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2006/ms06-077
http://www.vupen.com/english/advisories/2006/4970
http://www.us-cert.gov/cas/techalerts/TA06-346A.html
http://www.securityfocus.com/bid/21495
http://www.securityfocus.com/archive/1/454969/100/200/threaded
http://www.kb.cert.org/vuls/id/238064