From the article:

Internet Systems has published a report which shows that hackers and cyber criminals are developing malicious codes to exploit known vulnerabilities much faster than before. The X-Force Threat Insight Quarterly highlights that the number of vulnerabilities in 2005 has increased by over 33% over 2004.

Analysts from X-Force, the research and development team at ISS evaluated 4472 vulnerabilities in both hardware and software during 2005. From the public announcement of the vulnerability on the internet, the report highlights that 3.13% of threats discovered had malicious code that surfaced within 24 hours, whereas 9.38% had code that surfaced within 48 hours.

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