A Microsoft security report released on Monday warns that cyber crooks are digging into computers for weak spots to penetrate with worms — malicious software that steals control or data.

Rogue security software remained the top hacker threat to computers during the first half of this year, but the number of infections was dropping while penetrations by worms doubled, according to the Security Intelligence Report.

"We still see rogue security software in high volume but not on the rise," Microsoft Malware Protection Centre principal architect Jeff Williams told AFP. "What is on the rise is resurgence of worm activity, particularly Conficker and Taterf."

Worms are programmed to replicate themselves, wriggling from machine to machine by hiding in legitimate applications or piggy-backing on USB drives or other portable data storage devices.

Rogue security software, or "scareware," typically spreads by tricking people with pop-up boxes bearing bogus alerts that their machines are infected.

Spooked computer users are then enticed to pay for applications to fix the supposed computer problems. People that fall for the scam wind up paying hackers; providing them credit card information, and installing malware.

Automated scareware blocking in Web browsers and efforts by law enforcement agencies to crack down on companies peddling rogue security software has helped curb the threat.

"When selecting an anti-virus product, do it from a proven provider, not someone you never heard of who just pops up on your screen," Williams said.

The return of the worm

Improving defences of computers was seen as a reason hackers are reverting to worms, which were a top bane about a decade ago.

"We see a rise again in worms as profit-motivated criminals are digging deeper, finding more arcane vulnerabilities to execute remotely," Williams said.

A Conficker worm that plagued the Internet at the start of the year was so pernicious that a task force to combat it was formed by computer software and security firms.

Conficker and Taterf worms have reportedly wriggled into millions of machines.

One of the troublesome ways both worms spread is by stowing away on thumb drives, which are becoming increasingly popular vehicles for people to move music, videos, games, files or other data between computers.

"Think about how and where people play online games," Williams said. "What you tend to see is people remove a drive from home or an Internet kiosk and take it back into the enterprise (workplace)."

› Page 2: Better protection needed

AFP

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