Oracle has released a patch for fixing a critical venerability that could allow a denial-of-service (DoS) attack, for its Apache web server software.

The venerability affected versions httpd 2.0 or 2.2 and all other Oracle server products that were based on the software like Fusion Middleware, Application Server and Enterprise Manager.

The company explained in an alert issued to users that the flow could be remotely exploited without authentication and might also be exploited through a network without the need for a username and password.

"A remote user can exploit this vulnerability to impact the availability of un-patched systems. Due to the threat posed by a successful attack, Oracle strongly recommends that customers apply Security Alert fixes as soon as possible," the warning said.

The release is the fifth outside of the company's quarterly update schedule since 2005.