Bulletproof TLS Newsletter 
Bulletproof TLS Newsletter is a free periodic newsletter bringing you commentary and news surrounding SSL/TLS and Internet PKI, designed to keep you informed about the latest developments in this space. Maintained by Hanno Böck.
Current Issue
ALPACA shows TLS cross-protocol attacks
29 Jun 2021
A team of security researchers has shown vulnerabilities that affect the interaction of different TLS-protected protocols if they are operated with the same host name. They named the attacks ALPACA, and a paper will be published at the upcoming USENIX conference. The underlying issue is that traditionally TLS contains no protection against cross-protocol attacks.
The most impactful attacks the researchers were able to show affect the interaction of browser HTTPS connections and FTP. When an attacker has a user account on an FTP server operated on the same host as an HTTPS server, it’s possible to let the browser generate requests that the FTP server will interpret as valid commands. This allows triggering an upload that will contain the browser’s session cookies or a download that leads to a cross-site scripting vulnerability. The attacks on FTP are an extension of a previous attack discovered by Jann Horn in 2015.
Read MoreSubscribe to the Bulletproof TLS Newsletter
This subscription is just for the newsletter; we won't send you anything else.
Recent Issues
Designed by Ivan Ristić, the author of SSL Labs, Bulletproof SSL and TLS, and Hardenize, our course covers everything you need to know to deploy secure servers and encrypted web applications.
Remote and trainer-led, with small classes and a choice of timezones.
Join over 1,500 students who have benefited from more than a decade of deep TLS and PKI expertise.