Microsoft Downplays SQL Server Database Vulnerability

Microsoft is downplaying a SQL Server security flaw that could be exploited by someone with administrative privileges to see users' unencrypted passwords.

The vulnerability was discovered last year by database security vendor Sentrigo when one of their researchers noticed that the unique string of their personal password was visible in memory in SQL Server. Since then, it has touched off a bit of back-and-forth between the vendor and Microsoft, which contends the vulnerability is a non-issue because it requires administrative access.

While officials at Sentrigo concede that administrative access is necessary for an exploit to work, they also contend that many applications are deployed with administrative privileges – meaning that hackers could potentially use a SQL injection vulnerability to access administrative passwords.

"Passwords used to login to SQL Server are stored in memory in clear text," explained Sentrigo CTO Slavik Markovich. "These are not erased until SQL Server is restarted, so (they) may in many cases include passwords going back for weeks or months in production environments. It is a simple matter of dumping memory in byte format, and reviewing the contents looking for usernames, which will be followed by the password."

Compromising those passwords can have broad implications since many people use the same set of passwords for multiple systems, he added.

In the case of SQL Server 2000 and 2005, attackers can exploit the situation remotely. There is some mitigation for users of SQL Server 2008 however, because Microsoft removed the DBCC utility. Local connections however can still exploit the issue.

Despite this, Microsoft contends the vulnerability is much ado about nothing.

“Microsoft has thoroughly investigated claims of vulnerabilities in SQL Server and found that these are not product vulnerabilities requiring Microsoft to issue a security update,” a spokesman said. “As mentioned by the security researchers, in the scenario in question, an attacker would need administrative rights on the target system.”

“An attacker who has administrative rights already has complete control of the system and can install programs; view, change, or delete data; or create new accounts with full user rights,” the spokesman added.

While administrators can normally reset a user’s password if needed, best practices in security do not allow even administrators to see the actual passwords of other users, Sentrigo officials said.  This is an even greater problem as many enterprises need to comply with various standards and regulations that require strict segregation of duties, something that is clearly violated by sharing all users’ passwords with the administrators, Sentrigo contends.

In response to the situation, the security vendor has released a free utility to erase these passwords. The utility can be downloaded starting today from the company’s Web site.