New Version of Sober Worm Spreading in Europe

By Larry Seltzer  |  Posted 2004-04-05 Print this article Print

Worm comes in either German or English e-mail. Security companies raise threat levels.

A new variant of the Sober worm, Sober.F, is spreading in Europe, and some anti-virus companies are raising their threat levels for the worm due to its success. Sober.F arrives in an e-mail sent by the worms own SMTP engine. According to F-Secures description of the worm, the incoming message can have any of a large number of subject lines and message bodies, some in German and some in English.

The message also contains an executable file attachment, which, according to Symantecs analysis, contains any of a list of names with an .EXE extension and is 42,496 bytes large. When a user launches the attachment it sets itself to run automatically when Windows starts, then searches files on the hard disk to use as senders and recipients in the messages sent as it attempts to spread itself.

Symantec has raised Sober.F from a Level 2 to Level 3 threat severity, labeling it "either as highly wild (but reasonably harmless and containable) or potentially dangerous (and uncontainable) if released into the wild." Symantec has also increased its overall "ThreatCon" level from 1 to 2 out of concern that Sober.F is developing into a major outbreak. F-Secure classified the threat from Sober.F as "moderate."

Interestingly, F-Secure says that the worm checks the hard disk constantly for a file named ZHCARXXI.VVX. If it finds this file, it immediately unloads itself from memory. If the file is present during installation, the worm does not copy itself to the hard disk.

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Larry Seltzer has been writing software for and English about computers ever since—,much to his own amazement—,he graduated from the University of Pennsylvania in 1983.

He was one of the authors of NPL and NPL-R, fourth-generation languages for microcomputers by the now-defunct DeskTop Software Corporation. (Larry is sad to find absolutely no hits on any of these +products on Google.) His work at Desktop Software included programming the UCSD p-System, a virtual machine-based operating system with portable binaries that pre-dated Java by more than 10 years.

For several years, he wrote corporate software for Mathematica Policy Research (they're still in business!) and Chase Econometrics (not so lucky) before being forcibly thrown into the consulting market. He bummed around the Philadelphia consulting and contract-programming scenes for a year or two before taking a job at NSTL (National Software Testing Labs) developing product tests and managing contract testing for the computer industry, governments and publication.

In 1991 Larry moved to Massachusetts to become Technical Director of PC Week Labs (now eWeek Labs). He moved within Ziff Davis to New York in 1994 to run testing at Windows Sources. In 1995, he became Technical Director for Internet product testing at PC Magazine and stayed there till 1998.

Since then, he has been writing for numerous other publications, including Fortune Small Business, Windows 2000 Magazine (now Windows and .NET Magazine), ZDNet and Sam Whitmore's Media Survey.

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