Only if they have succedded in placing a particular script on your comp
in the Internet temp files................. it is possible but not so
easy to do
Personally I use online scanners as a last resort - especially if I am on someone else's computer trying to fix it and they do not have an AV problem installed or if it is playing up
Below is an email message I received from a virus research firm. What is alarming is the indications that a hacker can get into your system if you use a free website virus scan at two of the sites listed below. I use website virus all the time; usually housecall but occasionaly I use Panda (very very slow).
Researcher Claims Online Anti-virus Scanners Buggy
By Larry Seltzer
April 7, 2004
UPDATED: Online scanners from Symantec, McAfee and Panda all contain buffer overflows. One researcher claims an attacker could execute arbitrary code, another just that they could crash the browser. Panda reports their software has been fixed and Symantec and McAfee confirm the browser crash.
An Israeli security researcher claims to have found security holes in the free online scanners of three major anti-virus companies.
Rafel Ivgi, also known as "The Insider," in posts to several security mailing lists, claims that Panda ActiveScan, McAfee FreeScan, and Symantec Virus Detection all suffer from buffer overflows that could allow an attacker to crash the system and potentially execute arbitrary code.
Read more here: http://www.eweek.com/article2/0,1759,1563092,00.asp Copyright © 1996-2004 Ziff Davis Media Inc.
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