News

New Version of Bugbear Strikes

A variant of the Bugbear mass-mailing worm started hitting corporate networks late last week, prompting the first worm alert since Microsoft launched its Virus Information Alliance.

W32/Bugbear.B@MM spreads through e-mail and network shares. A complex piece of malware, Bugbear.B contains a mass-mailer, a network share propagator, a keylogger, a remote access trojan, a polymorphic parasitic file infector and a security software terminator.

The worm sends itself to addresses found on the local system in files and e-mail messages, and it spoofs e-mail addresses in the from field, as well. That means that the apparent sender of a Bugbear.B-infected e-mail isn't necessarily infected. Attachments carrying the worm's payload often have a double file extension.

While Microsoft rates the severity as "moderate" and Trend Micro calls it "medium" risk, McAfee assesses the risk as "high."

Microsoft posted an alert about Bugbear.B on Thursday on the virus information page that accompanies its Virus Information Alliance, which includes Network Associates and Trend Micro. The VIA launched last month. The virus page can be found at www.microsoft.com/technet/treeview/?url=/technet/security/virus/alerts/.

While the program is new, Microsoft's virus alerts are not. The Bugbear.B alert is Microsoft's fourth of the year. The company also alerted users to Slammer and Fizzer, and posted a warning about Palyh the same day as the Virus Information Alliance launched.

About the Author

Scott Bekker is editor in chief of Redmond Channel Partner magazine.

Featured

  • Microsoft Offers Support Extensions for Exchange 2016 and 2019

    Microsoft has introduced a paid Extended Security Update (ESU) program for on-premises Exchange Server 2016 and 2019, offering a crucial safety cushion as both versions near their Oct. 14, 2025 end-of-support date.

  • An image of planes flying around a globe

    2025 Microsoft Conference Calendar: For Partners, IT Pros and Developers

    Here's your guide to all the IT training sessions, partner meet-ups and annual Microsoft conferences you won't want to miss.

  • Notebook

    Microsoft Centers AI, Security and Partner Dogfooding at MCAPS

    Microsoft's second annual MCAPS for Partners event took place Tuesday, delivering a volley of updates and directives for its partners for fiscal 2026.

  • Microsoft Layoffs: AI Is the Obvious Elephant in the Room

    As Microsoft doubles down on an $80 billion bet on AI this fiscal year, its workforce reductions are drawing scrutiny over whether AI's ascent is quietly reshaping its human capital strategy, even as official messaging avoids drawing a direct line.