Risk
7/8/2013
11:48 AM
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.

The Syrian Electronic Army: 9 Things We Know
(click image for larger view)
The Syrian Electronic Army: 9 Things We Know
Cryptocat, a free tool designed to encrypt online chats, has been updated to fix errors that would have allowed an attacker to eavesdrop on chats. The vulnerability resulted from developers using below-minimum public key sizes or iterations. As a result, anyone who used a vulnerable version of Cryptocat to hold a group conversation, or who communicated with anyone using the software, could have had their communications easily intercepted.

That warning was sounded by security researcher Steve Thomas, who detailed the errors in a blog post. "If you used group chat in Cryptocat from Oct. 17th, 2011 to June 15th, 2013, assume your messages were compromised," he said. "Also if you or the person you are talking to has a version from that time span, then assume your messages are being compromised."

Thomas built a tool he calls DecryptoCat, which "cracks the ECC public keys generated by Cryptocat versions 1.1.147 through 2.0.41" in about a day, he said. Using the information generated by the tool, it would then take just a few minutes to crack any vulnerable Cryptocat key. Based on the coding errors he found, Thomas had harsh words for the chat tool's developers, who he labeled as being "incompetent." "I feel bad about calling them incompetent, but it is true. If you mess up in all the places I cared to check ... that's incompetence," he said.

[ Need an encryption how-to? Read 5 Rules For (Almost) Painless Encryption. ]

In response, Cryptocat issued an apology, and said that the bug detailed by Thomas -- which they claimed left users' communications vulnerable for only seven months -- was rapidly fixed. "The vulnerability was quickly resolved and an update was pushed," said the Cryptocat development blog post. "We sincerely thank Steve for his invaluable effort."

The developers emphasized that it's impossible to keep software entirely free from bugs. "Bad bugs happen all the time in all projects," they said. "Cryptocat is not any different from any of the other notable privacy, encryption and security projects, in which vulnerabilities get pointed out on a regular basis and are fixed. Bugs will continue to happen in Cryptocat, and they will continue to happen in other projects as well. This is how open source security works."

Previous
1 of 2
Next
Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Dark Reading Tech Digest, Dec. 19, 2014
Software-defined networking can be a net plus for security. The key: Work with the network team to implement gradually, test as you go, and take the opportunity to overhaul your security strategy.
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2011-1793
Published: 2014-12-25
rendering/svg/RenderSVGResourceFilter.cpp in WebCore in WebKit in Google Chrome before 11.0.696.65 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted SVG document that leads to a "stale pointer."

CVE-2011-1794
Published: 2014-12-25
Integer overflow in the FilterEffect::copyImageBytes function in platform/graphics/filters/FilterEffect.cpp in the SVG filter implementation in WebCore in WebKit in Google Chrome before 11.0.696.65 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified ...

CVE-2011-1795
Published: 2014-12-25
Integer underflow in the HTMLFormElement::removeFormElement function in html/HTMLFormElement.cpp in WebCore in WebKit in Google Chrome before 11.0.696.65 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a crafted HTML document con...

CVE-2011-1796
Published: 2014-12-25
Use-after-free vulnerability in the FrameView::calculateScrollbarModesForLayout function in page/FrameView.cpp in WebCore in WebKit in Google Chrome before 11.0.696.65 allows remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via crafted JavaS...

CVE-2011-1798
Published: 2014-12-25
rendering/svg/RenderSVGText.cpp in WebCore in WebKit in Google Chrome before 11.0.696.65 does not properly perform a cast of an unspecified variable during an attempt to handle a block child, which allows remote attackers to cause a denial of service (application crash) or possibly have unknown othe...

Best of the Web
Dark Reading Radio
Archived Dark Reading Radio
Join us Wednesday, Dec. 17 at 1 p.m. Eastern Time to hear what employers are really looking for in a chief information security officer -- it may not be what you think.