Limited Entropy Dot Com Not so random thoughts on security featured by Eloi Sanfèlix

4Oct/101

On Padding Oracles, CBC-R and timing attacks…

Posted by Eloi Sanfèlix

Somewhere before the weekend I was discussing about Padding Oracles with a friend and somehow it came up that there was no public tool using timing information for this kind of attacks.

I had seen that Thai and Juliano mentioned timing leaks in their talk at EkoParty, but since AFAIK there was no public tool available I decided to look into it. Also, some weeks ago I added the CBC-R encryption part to my scripts, in order to be able to encrypt arbitrary information as long as we are able to control the IV.

So in this post I'm going to write about these two things: CBC-R encryption and a web based padding oracle attack script using timing information.