A denial of service (DoS) attack is an incident in which a user or organization is deprived of the services of a resource they would normally expect to have. In a distributed denial-of-service, large numbers of compromised systems (sometimes called a botnet) attack a single target.

Although a DoS attack does not usually result in the theft of information or other security loss, it can cost the target person or company a great deal of time and money. Typically, the loss of service is the inability of a particular network service, such as e-mail, to be available or the temporary loss of all network connectivity and services. A denial of service attack can also destroy programming and files in affected computer systems. In some cases, DoS attacks have forced Web sites accessed by millions of people to temporarily cease operation.

Common forms of denial of service attacks are: Read More…

Attackers continue to target Adobe products because the software is widely used and not always upgraded with the latest Adobe updates. Security researchers have also been devoting a lot of time to finding vulnerabilities in the company’s software. While antivirus vendors push out signatures that can detect malware attempting to exploit vulnerabilities, experts warn that new malicious code is developed daily and not all attacks can be detected.

Adobe issued another advisory last Tuesday warning of ongoing PDF attacks targeting a zero-day vulnerability in Adobe Reader and Acrobat. Some security firms have detected limited email attacks containing malicious PDF files attempting to exploit a remote code execution vulnerability in Reader and Acrobat 9.2 and earlier versions.

Adobe has reportedly said it did not plan an emergency patch to repair the hole because it did not want to disrupt its quarterly update process.