Klez


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Klez

An email virus that exploits a vulnerability in the Internet Explorer browser and executes when the message is read or previewed. Possibly originating in China, several versions of the Klez worm have been introduced since late 2001. They deposit themselves in the PC's Windows directory with a random file name and set the Registry to launch at startup. Klez searches for email addresses in the infected machine, and, using its own Internet mail transmitter (SMTP engine), sends messages to those addresses with virus attachments and a variety of subject headers and body text. Thus, the same user can keep getting different Klez emails from the same source.

In addition, Klez grabs an email address in the infected machine and turns it into the "from" address. If your PC is virus free, but you get emails from others saying you are constantly infecting them, those emails are coming from some other infected PC that has your email address somewhere in the computer (address book, old message, etc.). In addition, if you keep getting returned, undeliverable messages you never sent, an infected PC is sending emails using your from address to recipients whose mail addresses are no longer valid. See email virus.
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The landscape has certainly changed since I was a kid, removing Klez from my mom's computer, unable to answer the question, "What does the person who created the worm gain from doing this?"
(82.) Gary Giddins, "Don Byron: Sketches of Klez," Village Voice, October 10, 1989, 76.
Worms are another type of devious program that, today, typically spread via e-mail or Internet chat programs With the help of unprotected users' address books, worms such as Klez spread explosively--disrupting networks and businesses.
FOLK & COUNTRY Mawkin Causley/A Touch of Klez: 7.30pm, The Yardbird, Paradise Place, Birmingham; Suzy Bogguss: Robin 2, Mount Pleasant, Bilston 01902 401211; Rea River Roots Club - Derek 'Snake' Angus: 8pm, Tower of Song, 107 Pershore Rd South, Kings Norton 0121 486 1300; Matt Tyler: 12pm, Arts Cafe, St Martin's Church, The Bullring, Birmingham.
In "Klez Goes to College," Hankus Netsky considers issues of reviving and transforming traditions in his discussion of Jewish klezmer music ensembles.
2001: Ramen, Sadmind, Sircam, Code Red II, Nimda and Klez all appear.
This technology makes it possible to stop infections of the types caused by malware such as BugBear, Nimda, Klez, SirCam or LoveLetter, even if these have not previously been identified.
One worm from the Mimail family, Mimail.j, returned to the ratings, overtaking Klez.h--a veteran in the virus ratings, which has already celebrated its second birthday.
The most damaging virus of all time is still the MyDoom worm followed by NetSky, SoBig and Klez.
TYPE OF THREAT ESTIMATED ECONOMIC DAMAGE Category Percent of survey Attack Damage Worms or Viruses 80% Klez $9.89B Denial-of-service attacks 40% Love Bug $9.63B Unauthorized data access 34% Code Red $2.88B Incorrect configuration 32% Yaha $2.51B Website penetration 29% SirCam $1.57B Theft of customer data 13% Melissa $1.22B Disclosure of customer 8% Slammer $1.16B Sources: 2003 survey by the Yankee Group of 404 security decision makers.
It overtook third place bug, Klez.H - which took 18 months to rack-up eight million copies - in only seven days.