Rogue SSL certificates issued for popular websites

Posted by   Virus Bulletin on   Mar 24, 2011

Certificates revoked, but browsers still need to be updated.

Comodo, a major vendor of SSL certificates, has admitted to one of its affiliates' servers being hacked, leading to nine rogue SSL certificates for popular domains to be issued.

SSL (secure socket layer) allows for traffic over the Internet that can not be intercepted by intermediates. HTTP over SSL (commonly known as HTTPS) is essential for confidential traffic, such as password and online banking details, between users and websites. More and more websites, including recently Facebook and Twitter, allow for all the traffic to be sent via HTTPS.

However, one of the weaknesses of the protocol is that it does not guarantee that the website is indeed the one it claims to be. That is why a number of trusted organisations, of which Comodo is one, sell certificates that provide proof to the user's browser that communication is happening with the right website.

A hacker trying to re-route traffic attempting to access a certain website (to instead go to a malicious site) - for instance by installing malware on a computer, or by hacking into DNS servers - is significantly more likely to succeed if they can obtain a certificate for the domain. This appears to have happened at Comodo, where certificates were issued for, among others, Google, Yahoo, Skype and Mozilla.

Certificate issuers have the option to revoke certificates and indeed, Comodo did so immediately upon discovering the hack. However, as pointed out by Sophos's Mike Wood in his VB2010 presentation on signatures, most browsers do not check for revoked certificates by default. It is thus both important and understandable that both Microsoft (whose Internet Explorer 9 does have the correct defaults) and Mozilla have released updates that recognize the rogue certificates.

In a statement on its blog, Comodo said the initial attack was performed from an IP address in Iran. While the company acknowledges that this may be a false trail laid by the attacker, it also points out that issuing rogue certificates, combined with re-routing traffic, may be a very useful tool for governments who want to spy on their citizens.

More at Kaspersky's Threatpost blog here and at Sophos's Naked Security blog here.

Posted on 24 March 2011 by Virus Bulletin

twitter.png
fb.png
linkedin.png
hackernews.png
reddit.png

 

Latest posts:

VBSpam tests to be executed under the AMTSO framework

VB is excited to announce that, starting from the Q3 test, all VBSpam tests of email security products will be executed under the AMTSO framework.

In memoriam: Prof. Ross Anderson

We were very sorry to learn of the passing of Professor Ross Anderson a few days ago.

In memoriam: Dr Alan Solomon

We were very sorry to learn of the passing of industry pioneer Dr Alan Solomon earlier this week.

New paper: Nexus Android banking botnet – compromising C&C panels and dissecting mobile AppInjects

In a new paper, researchers Aditya K Sood and Rohit Bansal provide details of a security vulnerability in the Nexus Android botnet C&C panel that was exploited in order to gather threat intelligence, and present a model of mobile AppInjects.

New paper: Collector-stealer: a Russian origin credential and information extractor

In a new paper, F5 researchers Aditya K Sood and Rohit Chaturvedi present a 360 analysis of Collector-stealer, a Russian-origin credential and information extractor.

We have placed cookies on your device in order to improve the functionality of this site, as outlined in our cookies policy. However, you may delete and block all cookies from this site and your use of the site will be unaffected. By continuing to browse this site, you are agreeing to Virus Bulletin's use of data as outlined in our privacy policy.