The search giant accidentally e-mailed the notorious "Kama Sutra" worm to subscribers of its Google Video e-mail list.
Three posts sent to the 50,000 subscribers of the Google Video Blog e-mail group included the W32/Kasper.A@mm mass mailing worm, according to Google.
Also known as the Kama Sutra worm, the security threat, while largely harmless, gained the moniker in February after being distributed disguised as e-mailed porn.
The company advised subscribers of the group to use an antivirus application to remove the worm. "We're taking steps to ensure this doesn't happen again," Google said in a statement addressed to users of the mailing list.
Google said it "used the situation as a reminder to all moderators to carefully review all messages before distributing them," according to the spokesperson.
A high-profile company such as Google isn't the first to inadvertently distribute something similar to users or customers, said Graham Cluley, senior technology consultant with security firm Sophos.
Some of the most well-known instances of mailing lists used to distribute security nastiness actually has come from security watchdogs.
Two years ago, Finnish-based security firm F-Secure discovered that the Netsky-B worm had been sent to members of its UK security list. Like Google, F-Secure said at the time it would tighten controls on how messages are approved.
Russian hackers had previously invaded a security mailing list run by that country's Kaspersky Labs, which accidently sent the Braid e-mail worm to subscribers.
Clulely said it's a reminder about internal processes. Any company that doesn't have processes in place about what can be posted to their mailing lists could also suffer.
Companies need to restrict mailing lists to only approved messages, he added. Such a measure would ensure "no malware has sneaked its way onto the wires."
Web 2.0 resources, such as blogs and mailing lists, are often the victims of social engineering tactics, according to Sophos.
In a similar security snafu, popular user-written resource Wikipedia fell victim last week to scammers. As internetnews.com reported, hackers created a page for the open encyclopedia's German edition warning of a new version of the Blaster virus. What seemed like a link to an antivirus tool was actually a virus.