SubSeven 2.2 makes Back Orifice look tame.
RAVI KIRAN
A new version of a Trojan horse program popular with computer
intruders was publicly released on the web Friday, and quickly put to
use by an eager underground.
Nearly thirty disguised copies of the newly-released SubSeven 2.2 were
already tempting netizens Monday afternoon, cloaked in filenames
promising sexually explicit videos and images, and offered up on
Usenet newsgroups that specialize in erotica, experts say.
SubSeven
"That's where the majority of these Trojans are posted," says Patrick
Nolan, virus researcher at Network Associates' McAfee AVERT Labs.
"This means that the hackers are aggressively promoting their
product."
Since its debut in February, 1999, SubSeven has become a favorite tool
of intruders targeting Windows machines. While less well-known among
outsiders than the mediagenic Cult of the Dead Cow's Back Orifice
2000, SubSeven victims currently outnumber Back Orifice victims by 100-
to-1, Nolan estimates, the program's popularity driven by the steady
support of its pseudonymous author, "Mobman."
"It has been an evolving Trojan since the early days," says Nolan. "By
comparison, Back Orifice is a one hit wonder."
Like other Trojans, SubSeven is divided into two parts: a client
program that the attacker runs on his own machine, and a server that
he must insinuate into a victim's computer through some subterfuge,
usually by misrepresenting it as an image file or an electronic
greeting card.
DDoS potential
Also like other Trojans, SubSeven can be used as perfectly benign
remote administration program, though the official SubSeven web site
unabashedly promotes it as an intrusion tool.
Once installed, SubSeven's friendly user-interface allows the attacker
to easily monitor a victim's keystrokes, watch a computer's web cam,
take screen shots, eavesdrop through the computer's microphone,
control the mouse pointer, read and write files, and sniff traffic off
the victim's local network.
A SubSeven server can also be programmed to announce itself over ICQ
or Internet Relay Chat (IRC), and groups of servers can be remotely
controlled as one. That makes the program particularly useful for
launching distributed denial of service attacks (DDoS), in which
constellations of systems are simultaneously directed to flood a
single site with an overwhelming volume of traffic, as happened to
Yahoo!, CNN.com, and other online giants in February 2000.
Last October, the FBI's National Infrastructure Protection Center
(NIPC) and Internet Security Systems (ISS) warned that another DDoS
attack may be imminent, after ISS spotted some 800 machines infected
with a SubSeven variant reporting for duty on IRC. The variant was
named DEFCON8, for the annual Las Vegas hacker convention, and
circulated as SexxxyMovie.mpeg.exe. The anticipated cyberattack never
came.
The new version of SubSeven offers script kiddies increased
flexibility in the user interface, a revamped mechanism for
customizing the server, and for the first time runs smoothly on
Windows NT and Windows 2000. The client is not downward compatible
with previous versions of the program, which may slow adoption, Nolan
says.
SubSeven 2.2 signatures will likely be quickly be integrated into
antivirus updates. In any event, users who don't accept executables
from strangers are safe from the Trojan.