Microsoft FREAK!
Action Required:
If you run a server …
You should immediately disable support for TLS export cipher suites. While you’re at it, you should also disable other cipher suites that are known to be insecure and enable forward secrecy. For instructions on how to secure popular HTTPS server software, we recommend Mozilla’s security configuration guide and their SSL configuration generator. We also recommend testing your configuration with the Qualys SSL Labs SSL Server Test tool.
If you use a browser …
Make sure you have the most recent version of your browser installed, and check for updates frequently. Updates that fix the FREAK attack should be available for all major browsers soon.
If you’re a sysadmin or developer …
Make sure any TLS libraries you use are up to date. Unpatched OpenSSL, Microsoft Schannel, and Apple SecureTransport all suffer from the vulnerability. Note that these libraries are used internally by many other programs, such as wget and curl. You also need to ensure that your software does not offer export cipher suites, even as a last resort, since they can be exploited even if the TLS library is patched. We have provided tools for software developers that may be helpful for testing.
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Microsoft has confirmed that its implementation of SSL/TLS in all versions of Windows is vulnerable to the FREAK encryption-downgrade attack.
This means if you're using the company's Windows operating system, an attacker on your network can potentially force Internet Explorer and other software using the Windows Secure Channel component to deploy weak encryption over the web.
Intercepted HTTPS connections can be easily cracked, revealing sensitive details such as login cookies and banking information, but only if the website or service at the other end is still supporting 1990s-era cryptography (and millions of sites still are).
"Microsoft is aware of a security feature bypass vulnerability in Secure Channel (Schannel) that affects all supported releases of Microsoft Windows," Redmond says in an advisory.
"Our investigation has verified that the vulnerability could allow an attacker to force the downgrading of the cipher suites used in an SSL/TLS connection on a Windows client system.
"When this security advisory was originally released, Microsoft had not received any information to indicate that this issue had been publicly used to attack customers."
The bug (CVE-2015-1637) in Windows' Secure Channel component is not thought to be under active attack by eavesdroppers at the time of writing.
The FREAK (Factoring attack on RSA-EXPORT Keys) mess revealed this week allows bad guys to decrypt login cookies and other sensitive information from HTTPS connections to vulnerable browsers.
Redmond is pushing out details of defensive mechanisms through its Microsoft Active Protections Program. It offers imperfect workarounds including changing of the registry in Server 2003 to disable vulnerable key exchange ciphers which it warns could cause "serious problems".
So far Google Chrome for OS X prior to version 41.0.2272.76 and BlackBerry OS 10.3 are known to be vulnerable. Users can visit freakattack.com to determine their browser exposure.
Most companies used 122 potentially vulnerable services, which pointed out that popular cloud services are disproportionately affected by slow patching against FREAK.