Borland Interbase backdoor exposed
Open source reveals foolishly hardcoded password
A back door password has been hidden in Borland/Inprise's popular Interbase database software for at least seven years, potentially exposing tens of thousands of private databases at corporations and government agencies to unauthorized access and manipulation over the Internet, experts say.
Analysts report that the account name 'politically' with the password 'correct' unlocks access to Interbase versions 4.0, 5.0 and 6.0 over the Net, and on any platform. Moreover, because Interbase has the ability to execute user-defined functions, the back door can be used to inject malicious code into a system, which could give an attacker administrative access to the computer itself, according to a Wednesday advisory from Carnegie Mellon University's Computer Emergency Response Team (CERT).
"The back door account password cannot be changed using normal operational commands, nor can the account be deleted from existing vulnerable server," the CERT warning states.
Jim Starkey, architect of the original, 1985 version of Interbase -- which did not contain a back door -- says hackers have already begun scanning the Internet for services on TCP port 3050, the default port for Interbase servers.
California-based Borland did not return phone calls, but the company Web site acknowledges "a potential security loophole within the Interbase product."
According to company press material, Interbase users include Nokia, MCI, Northern Telecom, Bear Stearns, the Money Store, the US Army, NASA, and Boeing.
Rather than reflecting the work of a disgruntled insider or saboteur, the secret password is a programmer's ill-advised solution to a software design problem, says Starkey, who has analysed the back door code.
Until 1994, Interbase did not have its own access control mechanism -- the software was protected by the password scheme built into the underlying operating system. But with version 4.0, engineers set out to change that.
"What they decided to do was to set up a special database on every system that contained all the account names and the encrypted passwords," says Starkey. That model created something of a chicken-and-egg problem: to authenticate a user, the system had to have access to the password database; but to access any database -- including the password database -- the user first had to be authenticated.
The unknown programmer's solution was to hardcode a special password into the software itself -- a secret shared by the client and server. The back door solved the problem, but was a devastatingly bad move from a security standpoint, says Bruce Schneier, CTO of Counterpane and author of Secrets & Lies: Digital Security in a Networked World.
"As long as nobody knows about this back door, it works. It's still secure," says Schneier. "But as soon as somebody finds out about it, everybody is immediately and irrevocably insecure."
Open Source led to exposure
Discovery became inevitable when Borland made Interbase open source last year, giving outsiders the chance to peer into its inner workings for the first time. German software developer Frank Schlottmann-Goedde spotted the hardcoded password in late December while working on the Firebird Project, a community open source project built on the Borland Interbase release.
"We reacted with horror," says Starkey. "Everyone had a real good idea of how easy it was to exploit."
Competing fixes are now available from Borland and the Firebird Project.
"The thing that everybody was worried about is that the word would get out that there was a problem before we had a solution," says Starkey. "The words 'politically correct' show up about eighteen places throughout the code."
The last back door to be reported in a major software release was in April, when the password 'wemilo' was found hardcoded into the small-business Internet shopping cart program Cart32, where it had gone undetected for five years.
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