The sys admin's daily grind: TLS Interposer
Rescuer at Hand
Many of the recent Linux exploits are the result of vulnerabilities in SSL libraries. TLS Interposer can help calm the waves.
The Poodle attack (Padding Oracle On Downgraded Legacy Encryption) relied on TLS implementations that failed to respond to requests from clients with new TLS versions. They then assumed that the server did not speak TLS at all and switched to the totally obsolete and vulnerable SSLv3. Attackers simply let TLS connections crash into the wall and cheered when the client dug out SSLv3.
Heartbleed was also an implementation error. It gave attackers the ability to read 64KB of the server's RAM – multiple times in succession – thus allowing certificate keys to fall into the wrong hands. Bruce Schneier said at the time that, on a scale of 1 to 10, this was a category 11 disaster [1].
Administrators can avoid all of this pain by keeping the TLS implementations on their servers up to date. But, what if you are forced to run applications that do not even support the latest TLS versions? True to the adage of "Never change a running system," many people stubbornly stick with Apache 2.2, or other services that are of value only to archaeologists.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia