Persons claiming to be with the Mexican arm of "hacktivist" group Anonymous said Friday they were scrapping plans to expose information about the Zetas drug cartel after a kidnap victim was released.

Twitter messages from the accounts @anonhispano and @IberoAnon said the Anonymous activist kidnapped in the eastern city of Veracruz was freed ahead of a November 5 deadline set by Anonymous to divulge Zetas links to politicians and others working with the crime gang.

Experts said there was no way to verify the authenticity of the announcement, but that these accounts had in the past correctly predicted cyber attacks on Mexican government websites.

The purported Anonymous members also said in a statement to the "anonopsibero" blog that they had suspended "Operation Cartel" due to Zetas threats to innocent people.

"The Anonymous collective has decided by consensus that the information that we have will not be disclosed for now, as we cannot ignore threats involving innocent civilians," the statement said.

There was no comment from Mexican authorities, who previously indicated they could not verify the abduction.

In early October, the US security consultancy Stratfor said a video had circulated in which a masked individual claiming to be part of Anonymous had threatened to make some information public about the Zetas in retaliation for the kidnapping of an associate.

The Zetas emerged from a military arm of the Gulf cartel, and are among the main drug organizations involved in Mexico's bloodbath in recent years.

More than 45,000 people are believed to have been killed since 2006, when the government launched a massive military crackdown against powerful drug cartels battling among themselves over the lucrative drug trade.

Microsoft offering defenses against Duqu virus
San Francisco (AFP) Nov 4, 2011 - Microsoft on Friday was advising companies how to defend against infection by a Stuxnet-like Duqu virus.

The US technology colossus released the "workaround" along with detailed information it said would enable anti-virus software companies to detect Duqu, which takes advantage of a flaw in Windows computer operating systems.

"To make it easy for customers, we have released a fix-it that will allow one-click installation of the workaround and an easy way for enterprises to deploy," said Microsoft trustworthy computing group manager Jerry Bryant.

"Our engineering teams determined the root cause of this vulnerability, and we are working to produce a high-quality security update to address it," he said in a security advisory posted online.

A software patch to protect against Duqu will not be ready in time for this month's "update Tuesday" next week, according to Microsoft.

Duqu can sneak into computers by hiding in Word document files opened as email attachments.

Duqu infections have been reported in a dozen countries including Iran, France, Britain and India, according to US computer security firm Symantec.

The virus takes advantage of a previously unknown vulnerability in a Windows font-parsing engine to plant malicious code in the heart of a computer system, according to Microsoft.

"An attacker who successfully exploited this vulnerability... could then install programs; view, change, or delete data; or create new accounts with full user rights," Microsoft warned in a security advisory.

"We are aware of targeted attacks that try to use the reported vulnerability; overall, we see low customer impact at this time," it said.

Stuxnet was designed to attack computer control systems made by German industrial giant Siemens and commonly used to manage water supplies, oil rigs, power plants and other critical infrastructure.

Most Stuxnet infections have been discovered in Iran, giving rise to speculation it was intended to sabotage nuclear facilities there.