Feeds

Critical flaw exposes Oracle database passwords

Vuln leaves barn door open to brute-force attacks

Build a business case: developing custom apps

A security researcher says some versions of the Oracle database contain a vulnerability so serious that anyone with access to the server over a network can crack database passwords using a basic brute-force attack, given nothing more than the name of the database and a valid username.

"This is a critical issue because it's very easy to exploit, and it doesn't require any privileges," AppSec's Esteban Martinez Fayó said in an interview with Dark Reading.

According to a report issued on Thursday by Kaspersky Labs' Threatpost, the vulnerability stems from a fundamental flaw in the logon authentication protocol used by Oracle Database 11g Releases 1 and 2.

Normally, Oracle databases maintain connections with clients by issuing each a unique value known as a Session Key. But affected versions of Oracle 11g send the Session Key before the user is fully authenticated. As a result, an attacker can send a username, receive a Session Key, then hang up the connection and use the Session Key to guess the user's password.

"The attacker can perform a brute force attack on the Session Key by trying millions of passwords per second until the correct one is found," Fayó said, adding, "This is very similar to a SHA-1 password hash cracking."

According to Fayó, he and his team first alerted Oracle to the bug in May 2010. It was fixed in mid-2011, he says, but the patch was not included in a Critical Patch Update, and it only solved the problem by issuing a new, incompatible version of the authentication protocol, version 12.

Even when the patch is applied to a database, it will still use version 11.1 of the protocol by default. To get up and running with version 12, database servers and clients must both be patched, which means a large number of organizations are still using version 11.1 – and are therefore still vulnerable.

According to Fayó, Oracle currently has no plans to patch version 11.1 of the protocol to fix the flaw, and they aren't doing much to help customers migrate to version 12, either.

"The only comment from them was a paragraph about a new protocol fixing some security issues," he said. "They haven't said anything that made people aware to update the database and all of the database clients."

Mind you, brute-force attacks are not the easiest way to crack a password, since they essentially involve exhausting every possible combination of characters until the right combination is found. And Fayó says advanced cracking techniques, such as rainbow tables, can't be used to exploit this vulnerability, because of the way Oracle's cryptography is designed.

Still, he says, GPU acceleration and hybrid dictionary attacks can speed up the process of guessing passwords considerably, and Fayó has developed a proof-of-concept attack that can crack eight-character Oracle passwords in around five hours using standard CPUs.

In lieu of a fix from Oracle, Fayó recommends several work-arounds. One is to wrap database connections in some additional form of authentication, such as SSL or directory services. Another is to disable version 11.1 of the authentication protocol altogether and use an earlier version, such as 10g, which isn't vulnerable. ®

The essential guide to IT transformation

More from The Register

next story
Rupert Murdoch says Google is worse than the NSA
Mr Burns vs. The Chocolate Factory, round three!
e-Borders fiasco: Brits stung for £224m after US IT giant sues UK govt
Defeat to Raytheon branded 'catastrophic result'
Germany 'accidentally' snooped on John Kerry and Hillary Clinton
Dragnet surveillance picks up EVERYTHING, USA, m'kay?
Snowden on NSA's MonsterMind TERROR: It may trigger cyberwar
Plus: Syria's internet going down? That was a US cock-up
Who needs hackers? 'Password1' opens a third of all biz doors
GPU-powered pen test yields more bad news about defences and passwords
Think crypto hides you from spooks on Facebook? THINK AGAIN
Traffic fingerprints reveal all, say boffins
Microsoft cries UNINSTALL in the wake of Blue Screens of Death™
Cache crash causes contained choloric calamity
prev story

Whitepapers

Endpoint data privacy in the cloud is easier than you think
Innovations in encryption and storage resolve issues of data privacy and key requirements for companies to look for in a solution.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Solving today's distributed Big Data backup challenges
Enable IT efficiency and allow a firm to access and reuse corporate information for competitive advantage, ultimately changing business outcomes.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.