Sdbot.ftp is the script that the Sdbot family of worms uses to download themselves onto computers via FTP. Its highest infection rates are currently being recorded in Chile, Poland and Mexico.
"September has followed the same trends as observed in previous months, characterised by a lack of massive epidemics, albeit without any decrease in the activity of internet threats," said Panda in a statement.
In second place was Netsky.P, a worm that exploits a vulnerability in Internet Explorer to run itself automatically. The Jupillites.G, Torpig.A and Torpig.DJ Trojans fill out the top five.
Tearec.A, better known as Kama Sutra, one of the most frequently detected malicious codes in 2006, is still in the chart in sixth place. The virus disables certain antivirus programs and attempts to delete files and P2P programs.
Also in the top 10 were Bagle.pwdzip, Puce.E, Qhost.gen and Parite.B. The latter is designed to infect files with EXE and SRC extensions.
Panda ActiveScan reported that there remains a persistent danger of software vulnerabilities.
"The presence of Netsky.P, which exploits a software vulnerability resolved more than five years ago, highlights just how many computers are not up to date, " said the security firm.
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