The RPC DCOM interface in Windows 2000 SP3 and SP4 allows remote attackers to cause a denial of service (crash), and local attackers to use the DoS to hijack the epmapper pipe to gain privileges, via certain messages to the __RemoteGetClassObject interface that cause a NULL pointer to be passed to the PerformScmStage function.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A494
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A1118
https://docs.microsoft.com/en-us/security-updates/securitybulletins/2003/ms03-039
http://www.kb.cert.org/vuls/id/326746
http://www.cert.org/advisories/CA-2003-23.html
http://www.cert.org/advisories/CA-2003-19.html
http://marc.info/?l=bugtraq&m=105880332428706&w=2
http://lists.grok.org.uk/pipermail/full-disclosure/2003-July/006851.html