January 2001 Virus “Hits”

Anti-virus software developer Sophos has published the latest monthly top-ten list of the most frequently occurring viruses, worms, and Trojans. The list is as follows, with the most frequent virus, according to percentage, occupying the number one spot, and so on.

Taking over the top spot is a variant of the Windows 32 Navidad worm, Win32.Navidad.B, at a staggering 20.7%. Dropping one notch from last month’s number one showing is I-Worm.MTX (a.k.a. Apology) at 14.8%. Appearing at number three is the first of three representatives from the I-Worm.Hybris family Hybrys.B at 13.7%, with Hybris.C coming in at six at 5.0% and Hybris.C at 2.0% in the number eight slot. WScript.KakWorm moves up one to number four at 7.6%, and I-Worm.Prolin drops from two to five at 5.4%.

The rest of the top ten is rounded out by: I-Worm.LoveLetter variant LoveLetter.AS at 3.4%; Worm.Qaz making a reappearance in the top ten at 2.0%; and Worm.RC5.b (a.k.a. Bymer.A) taking the ninth spot at 1.9%.

The rest of the list contains various viruses comprising the remaining 23.5% of occurrences.

Be sure to tune in next month to find out about the newest chart toppers for February.

Kaspersky researchers have discovered new Mirage Kitten attacks using previously undocumented malware families: NodeRabbit in Node.js and PollCat in JavaScript.

Our experts discovered a new CoolClient backdoor variant with a kernel-mode rootkit driver that hides malicious processes, files, and network connections from security tools and threat analysts.

Kaspersky experts break down a new Armored Likho campaign that poses as a fundraising efforts and delivers a new Still Toolkit aimed at stealing Telegram data and eavesdropping on victims.

Kaspersky researchers reveal previously undocumented malware attributed to Mirage Kitten (UNC1549, Smoke Sandstorm, Nimbus Manticore): NightLedger backdoor, ArcBridge, and BridgeHead tunneling tools.