Reported December 20, 2001, by eEye Digital Security.
Microsoft Windows XP
Microsoft Windows ME
Microsoft Windows 98/98SE
Multiple vulnerabilities exist in Microsoft's implementation of Universal Plug and Play (UPnP). The first vulnerability is a remotely exploitable buffer overflow that can result in system-level access to the vulnerable host. This vulnerability results from an unchecked buffer in one of the service’s components that handles notify directives. By sending malformed UPnP notify directives generated at various intervals, a attacker can cause access violations on the vulnerable system, which results in pointers being overwritten. Because the UPnP service runs with SYSTEM privileges, a hacker can gain complete control of the system remotely.
The second vulnerability involves a variant of this first vulnerability in that the UPnP service doesn't take sufficient steps to limit how far the service goes to obtain information about a discovered service. Two Denial of Service (DoS) scenarios exist for exploiting this vulnerability. The first is that a potential attacker could send a notify directive to a vulnerable host and loop the request. This loop would eventually consume all system resources on the vulnerable system. The second scenario involves specifying a third system in the notify directive for the vulnerable system(s) to respond to. As the UPnP service responds to both multicast and broadcast UDP requests, the potential for Distributed Denial of Service (DDoS) attacks exist. You can find specific details about these vulnerabilities at the discoverer’s Web site.
The vendor, Microsoft, has released security bulletin MS01-059 to address these vulnerabilities and recommends that affected users immediately apply the patch provided at this URL. The company further recommends that affected users follow the common practice of placing a firewall on ports 1900 and 5000 to further mitigate this risk.