I have seen a number of these. In every case I have found on our campus, there was a user account with power user or administrative access that had an extremely weak password. The intruder would "net use" through that account to create another admin account (support in this case) for him to use. They would update the security policy so that other intruders are unlikely to compromise the system. And then they would start up Terminal services or similar remote desktop utilities, and set up either a warez server or irc serv-u daemon with an innocuous looking name like winasp, lsasss.exe, wimlogon.exe or something else that looks close to actual legit processes. I would check to verify that all the accounts have appropriately significant passwords on them. Also, I would check the event log to see if there is a gapping hole in time where logged entries do not exist any more. This is the first i have seen exactly like this, but it is similar enough to ones i have been fighting on campus for the past few months to call it coincidence. Scott Fendley On Thu, 2 Jan 2003, Ostfeld, Thomas wrote: > One of my web servers appears to have had an intrusion. The box is Win2k > Advanced Server, SP3, up to date on all security patches. I first became > aware of a problem when the main website hosted on the box became > inaccessible. Checking the machine, I discovered that the Local Security > Policy had been altered as to remove the Everyone and Local Administrators > group from "Access this machine from the network" policy In place was a > single local account called "Support" that I did not recognize. > > Looking into the accounts database, I discovered this account with a > description of "Built in account for providing user support." It was also > part of the administrators group. Needless to say, this looked suspicious, > so I locked the server back down and set up intrusion detection to look for > further attempts to exploit the account. > > I know approximately when the attack occurred, but I am still puzzled as to > how it was done. The web logs show the usual IIS root exploit attempts, but > those all fail. Everything else looks normal. I've scoured the machine > pretty thoroughly for bots, trojans, viruses, hidden and altered files, and > have so far come up empty. No weird open ports either. > > Has anyone seen this before? There is one or two postings of the same > nature on Google, but little else to give me something to go on. > > Tom Ostfeld > Knowledge Impact > Ostfeld7 (AIM) > > > ---------------------------------------------------------------------------- > This list is provided by the SecurityFocus ARIS analyzer service. > For more information on this free incident handling, management > and tracking system please see: http://aris.securityfocus.com > > ---------------------------------------------------------------------------- This list is provided by the SecurityFocus ARIS analyzer service. For more information on this free incident handling, management and tracking system please see: http://aris.securityfocus.com
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