Risk
7/8/2013
11:48 AM
Connect Directly
RSS
E-Mail
50%
50%

Encrypted IM Tool Vulnerable To Eavesdropping

Bugs in instant messaging encryption tool Cryptocat left users' group chats vulnerable to eavesdropping for over a year, says security researcher.

Even so, the developers said they'd revamped their messaging to would-be users. "We've added a new, more visible warning about Cryptocat's experimental status to our website!" the group tweeted Sunday. Likewise, the website where the software may be downloaded sports the following warning: "Cryptocat is not a magic bullet. You should never trust any piece of software with your life, and Cryptocat is no exception."

Thomas acknowledged that the developers' fix corrected the problem his DecryptoCat tool exploits. "For Cryptocat version 2.0.42 this will take 1,000 computer-years to generate [cracked keys], 500 computer-years on average to use, and 40 petabytes to store," he said. "So the only ones capable of doing this are large companies and governments."

Is Cryptocat now safe to use? In fact, Thomas said his bug report wasn't meant to be exhaustive, and warned against relying on the application for encrypted communications. "I'm sure there are plenty of bugs and other bad crypto in other parts because I only looked at random generation and found a bug, at public key algorithm and found a bug, and quickly looked where random is used and found something scary, and random (BigInt.randBigInt) used in two-party messaging and found a bug," he said.

The exploitable Cryptocat vulnerabilities are notable, given that interest in using encrypted communications tools has been growing in the wake of leaks by former National Security Agency (NSA) contractor Edward Snowden, who revealed the existence of numerous NSA data and metadata-interception programs.

But ensuring that communications can't be intercepted depends in large part on the applications not including exploitable vulnerabilities or bugs. For example, Bruce Schneier, chief security technology officer of BT, Monday detailed four techniques for protecting communications against snooping: use vulnerability-free applications, choose secure passwords, manage those passwords securely and know the threat you're facing.

Although Schneier's advice pertained to securing email, it also applies to chat -- and it's notable that the first tip is to use applications that don't include vulnerabilities. His reasoning is simple: No matter how great the cryptography used by an application, if someone wants to intercept messages sent using that application, they're going to first see if "breaking the engineering" might suffice. In the case of Cryptocat, prior to the patch, that would have been the case.

Then again, according to leaked NSA docs, the agency is legally allowed to retain encrypted communications indefinitely, meaning that simply by using an application such as Cryptocat, people might already be putting themselves at greater risk of having their communications intercepted and studied. Thus, anyone who used a vulnerable version of Cryptocat might have had their encrypted communications stored. With Thomas' bug information in hand, decrypting those messages would now be a trivial task.

Previous
2 of 2
Next
Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
Partner Perspectives
What's This?
In a digital world inundated with advanced security threats, Intel Security seeks to transform how we live and work to keep our information secure. Through hardware and software development, Intel Security delivers robust solutions that integrate security into every layer of every digital device. In combining the security expertise of McAfee with the innovation, performance, and trust of Intel, this vision becomes a reality.

As we rely on technology to enhance our everyday and business life, we must too consider the security of the intellectual property and confidential data that is housed on these devices. As we increase the number of devices we use, we increase the number of gateways and opportunity for security threats. Intel Security takes the “security connected” approach to ensure that every device is secure, and that all security solutions are seamlessly integrated.
Featured Writers
White Papers
Cartoon
Current Issue
Dark Reading's October Tech Digest
Fast data analysis can stymie attacks and strengthen enterprise security. Does your team have the data smarts?
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2014-4448
Published: 2014-10-22
House Arrest in Apple iOS before 8.1 relies on the hardware UID for its encryption key, which makes it easier for physically proximate attackers to obtain sensitive information from a Documents directory by obtaining this UID.

CVE-2014-4449
Published: 2014-10-22
iCloud Data Access in Apple iOS before 8.1 does not verify X.509 certificates from TLS servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.

CVE-2014-4450
Published: 2014-10-22
The QuickType feature in the Keyboards subsystem in Apple iOS before 8.1 collects typing-prediction data from fields with an off autocomplete attribute, which makes it easier for attackers to discover credentials by reading credential values within unintended DOM input elements.

CVE-2012-5242
Published: 2014-10-21
Directory traversal vulnerability in functions/suggest.php in Banana Dance B.2.6 and earlier allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the name parameter in a get_template action.

CVE-2012-5243
Published: 2014-10-21
functions/suggest.php in Banana Dance B.2.6 and earlier allows remote attackers to read arbitrary database information via a crafted request.

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Follow Dark Reading editors into the field as they talk with noted experts from the security world.