Symantec: Security Flaws Exploited Much FasterSymantec: Security Flaws Exploited Much Faster

The only good news in this week's report from security-software vendor Symantec Corp. is that the rate at which Internet security holes are found leveled off at seven per day in the last six months of 2003. The bad new is that those flaws are being exploited much more quickly.

A prime concern of security pros is the time from when a vulnerability is disclosed publicly--often by software makers, who publish a patch at the same time--and when writers of worms or virus write malicious code to exploit it.

"We looked at the life cycle from vulnerability to attack, and we could see there that the speed is consistently getting faster and faster," says Vincent Weafer, senior director of Symantec Security Response. Symantec didn't quantify the average response, but cited examples to support the conclusion. Weafer compares the three weeks it took for the Blaster worm to emerge last August to the three days that elapsed between the recent leak of Microsoft source code onto the Net and an attack based on that code.

The compressed time leaves businesses increasingly vulnerable, since days or months can pass before patches get deployed at a typical company.

Compounding the problem is the fact that blended threats, such as viruses that install backdoors for hackers after a successful infection, are on the rise. These attacks tend to be more sophisticated and more damaging. The report notes that blended threats make up 54% of the top 10 malicious code submissions the company received in the latter half of 2003. Of the top 50 malicious code submissions, backdoor-capable code in particular increased 123%.

These backdoors can be used for hackers to steal confidential information or hijack a machine and force it to participate in a denial-of-service attack or to send spam. This trend seems to be confirmed by the findings of anti-spam vendor MX Logic Inc.: 30% to 50% of spam comes from infected hosts, it estimates.