FastPatch for (a) PatchLink Update Server (PLUS) before 6.1 P1 and 6.2.x before 6.2 SR1 P1, and (b) Novell ZENworks 6.2 SR1 and earlier, does not require authentication for dagent/proxyreg.asp, which allows remote attackers to list, add, or delete PatchLink Distribution Point (PDP) proxy servers via modified (1) List, (2) Proxy, or (3) Delete parameters.