Oracle issued a small, critical security patch Tuesday with 36 bug fixes covering several elements of its product line, including Oracle E-Business Suite and J.D. Edwards applications and the WebLogic Application Server.

But for the first time, three of the fixes with the highest vulnerability rating, 10, were for the core Oracle Database Server itself. The ratings are set by a government, university and industry group as the Common Vulnerability Scoring System.

Oracle discloses the rating to DBA's to help them assess how quickly they need to address the fixes in the patch. The 10 rating indicated three of the fixes addressed security exploits that could be executed by a hacker at a remote location with no claim to a proper user authentication.

Three other fixes were for the database server, although their CVSS ratings were less severe at 6.5. The versions of the database server affected included Oracle 11g release 11.1.0.7; Oracle 10g Release 2, including the 10.2.0.3 and 10.2.0.4 releases; Oracle 10g Release 10.1.0.5; and Oracle 9i Release 2, including 9.2.0.8 and 9.2.0.8DV.

Oracle security patches are issued each quarter on the Tuesday closest to the 15th of the month. Oracle recognizes outsiders who contribute to the patches, and Tuesday's critical update recognized Aviv Pode, head of security research at security firm Sentrigo, and Yaniv Azaria, a researcher in the Application Defense Center lab of the security firm, Imperva.

Imperva CTO Amachai Shulman said Tuesday patch was a case of Oracle fixing for a second time a bug that Imperva discovered a year ago. One of the lower-rated vulnerabilities was exposed by Imperva last fall and Oracle announced a fix. The problem reappeared in Tuesday's critical patch as vulnerability CVE-2009-2001, which was labeled a medium risk at 6.5, under the CVSS ranking system. It is a PL/SQL exploit caused by a buffer overflow.

In some cases, a hacker using PL/SQL can enter instructions in a form by filling its underlying buffer beyond what the form requires. The database system, seeking the expected user entry, gets an instruction attacking the database instead.

Imperva "reported the problem a year ago," said Shulman. Oracle fixed the symptom "but not the root cause, leaving a way to successfully attack the database with a buffer overflow," he said in an interview. But this exposure was not subject to exploitation by a remote user lacking authentication, hence its 6.5 rating, he said.

"I don't think during the four years critical patches have been issued that any exposure to the databse server scored a ten. This time there were three of them," he said.

A rating of 10 from the Common Vulnerability Scoring System means it is in the "high" severity range of the ratings, with any rating between 7-10 considered high. Medium severity is rated at 4 -6.9 and low severity at 1-3.9. The CVSS system was set up by the National Institute of Standards and Technology, Carnegie Mellon University and security specialists in the computer industry. The group calls itself the Forum of Incident Response and Security Teams.

Oracle representatives could not be reached for comment.

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