To: Bazmataz who wrote (29688 ) 8/22/1999 5:50:00 PM From: FuzzFace Respond to of 41369
Is AOL Hacking Its Own Instant Messaging Users? From: zdnet.com AOL may have more control over your computer than you do. By David Raikow, Sm@rt Reseller As the Instant Messaging (IM) war rages on, evidence is mounting which suggests that AOL is using a security hole in its own software to lock out IM clones. While security experts are still examining IM logs to determine precisely what is going on, it looks like AOL's tactics may have put its own users at serious risk. The first hint of a problem came last Wednesday, when an individual identifying himself as "Phil Bucking" of "Bucking Consulting" sent an email to PharLap Software president Richard Smith warning of a "buffer overflow" vulnerability in the AOL IM client. Smith, a noted security expert, quickly determined that the email had been falsified, and had almost certainly come from within Microsoft. Microsoft has flip-flopped on whether or not the email message actually came from one it its employees. Because of the identity question, "Mr. Bucking"'s allegations initially garnered little serious attention. On Monday, however, Robert Graham, chief technical officer with Network Ice Software, a software security firm, released a detailed analysis of the AOL IM logon procedure, which suggests a vulnerability almost identical to that described by "Bucking". A Very Serious Threat The security community is now taking the threat very seriously. "Buffer overflow" vulnerabilities allow an intruder to trick a susceptible machine into executing code by sending it more information than it is configured to receive. These attacks require a great deal of technical knowledge to develop, but are often automated with script tools and used to compromise network servers by skilled hackers and "script kiddies" alike. While emphasizing that the evidence is still preliminary, PharLap's Smith said he believes that AOL has been using this technique to trigger specific responses from its IM clients. Because Microsoft's IM clients do not have this bug, AOL servers can identify them, and lock them out of the system. This bug has only been observed on Windows clients; it is not clear how other platforms are affected. Smith said he sees this as a very serious potential threat to users. As Microsoft continually updates its clients, AOL must keep introducing new variations on the buffer overflow to stay ahead. "It's only a matter of time before they make a mistake, and machines running AOL IM start crashing all over the 'net," Smith predicts. Smith added that the hole gives AOL an extraordinary amount of power over users machines. "Remember that this is a technique normally used by hackers to break into machines. The current use seems pretty benign, but AOL can use this to execute any arbitrary code on a Windows machine--run software, leave backdoors, whatever. What happens if a disgruntled AOL employee finds a use for this?" Smith warned. Graham said he concurs with Smith's assessment, though he sees an even larger potential danger: "If hackers managed to masquerade as an AOL server, they could do anything to the target machine. This could be a real problem for cable modem and DSL users, who have 24 hour connections and are vulnerable to 'man-in-the-middle' attacks." Graham noted that such attacks are unlikely in the near future because of the technical expertise required, but are a very real possibility. "We will not discuss the methods we use to defend our users against attacks by Microsoft on our system," responded AOL spokesman Andrew Weinstein. "Our top priority is our users security, privacy, and safety, and we would never do anything to compromise that committment."