Time to FREAK out? How to tell if you're vulnerable
- 05 March, 2015 06:05
Nervous about the FREAK flaw? Freakin' out?
Not everyone is vulnerable to the potential attack vector that researchers from INRIA, a French research institute, and Microsoft disclosed yesterday.
Browsers running in Windows, for example, including Internet Explorer 11 (IE11), are immune to the threat.
The flaw affects SSL (Secure Sockets Layer) and its successor, TLS (Transport Layer Security) -- the protocols used to encrypt traffic between browsers and website servers. By interposing themselves between users and servers, typically via a classic "man-in-the-middle" (MITM) attack at a public Wi-Fi hotspot, hackers can leverage the long-standing weaknesses in SSL and TSL to intercept and read that supposedly-secure traffic.
But are your browsers vulnerable? What about the websites you frequent?
There are easy ways to check.
FREAKin' attack. On the client side, you can verify whether your browser(s) are vulnerable by heading to freakattack.com. A message will appear, either "Good News! Your browser appears to be safe from the FREAK Attack!" or "Warning! Your client is vulnerable to CVE-2015-0204. Even though your client doesn't offer any RSA EXPORT suites, it can still be tricked into using one of them. We encourage you to upgrade your client."
FREAKin' Web servers. Testing servers is more tedious. The INRIA and Microsoft researchers published a list of websites that were vulnerable as of early Tuesday; the list is not only very long, but organized by Alexa's website rankings, not alphabetically.
You can test your most-frequented websites yourself.
Qualys' SSL Labs boasts an SSL Server Test that will, with a little effort, tell you if the website's server supports "export-grade" cipher suites, which are at the root of the vulnerability.
Enter a domain name of any website into the SSL Server Test's field, then examine the resulting report. (Popular sites will likely have an already-run recent test that you can call up.) Look for the section of the report titled "Cipher Suites."
If there are listings with the word "EXPORT," as in, "TLS_RSA_EXPORT_WITH_DES40_CBC_SHA," the server supports export-grade cipher libraries, and so is vulnerable.
FREAKin' vulnerability. A vulnerable server does not necessarily mean that traffic between your browser and the website can be sniffed.
Both the browser and the server must support the export-grade cipher suites in order for an attack to be successful. "You are vulnerable if you use a Web browser that uses a buggy TLS library to connect, over an insecure network, to an HTTPS server that offers export cipher suites," the researchers wrote in a summary of their findings.
So even if you're connecting to sec.gov, the website of the U.S. Securities and Exchange Commission, and one of the sites that supports export cipher libraries (as of early Wednesday), you're safe if you're using, say, Chrome on OS X, because the latter does not support export suites. Only if both ends are insecure -- such as a Safari-to-sec.gov connection -- are you vulnerable.
Okay, now what?. Websites will have to update their servers, so there's nothing for you to do.
On the browser side, Apple has said it will push out a fix for Safari on OS X and iOS next week, while Google has crafted a patch and handed it to mobile carriers and device makers that support and sell Android smartphones and tablets. Because those carriers and device manufacturers, not Google, are responsible for patching the Android browser, it could be months, if ever, before users are secure.
Google launched Chrome in 2012 as a replacement for the stock browser -- which is still pre-loaded by many device makers, including Samsung -- to, among other things, circumvent its partners' sluggishness.