Threat Update | Logjam Vulnerability
May 20, 2015
What is Logjam?
Logjam is a browser and website encryption vulnerability that allows attackers to view encrypted content by downgrading security connections.
How does this vulnerability work?
When websites and mail servers attempt to communicate security with end users many of them do what is known as a Diffie-Hellman key exchange in an attempt to establish an encrypted connection. The Logjam attack allows man-in-the-middle attackers to downgrade vulnerable TLS connections to 512-bit export-grade cryptography. This downgraded connection would make it possible for hackers to decrypt the traffic.
Herjavec Group has not seen reports of hackers leveraging this technique to date.
We recommend that HTTPS services utilize at minimum a 1024- bit key.
A patch has been released for Internet Explorer and more are forthcoming for other browsers. Please ensure your organization is using the latest version of your applicable browser. Herjavec Group will continue to monitor this vulnerability and notify our customers of appropriate developments.