From ba39aef6738f8a1c6ce9ba817cbd99c59eb7a6b0 Mon Sep 17 00:00:00 2001 From: Jaromil Date: Sun, 23 Nov 2014 15:31:14 +0100 Subject: [PATCH] considerations on password bruteforce vulnerability on steghide --- KNOWN_BUGS.md | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/KNOWN_BUGS.md b/KNOWN_BUGS.md index 7614450..fee8d21 100644 --- a/KNOWN_BUGS.md +++ b/KNOWN_BUGS.md @@ -1,3 +1,28 @@ +# Vulnerability to password bruteforcing +## Issue affecting keys used in steganography + + An important part of Tomb's security model is to *make it hard for + attackers to enter in possession of both key and data storage*: once + that happens, bruteforcing the password can be relatively easy. + + Protection from bruteforcing is provided by the KDF module that can + be optionally compiled in `extras/kdf-keys` and installed. + + If a key is buried in an image and then the image is stolen, the KDF + protection does not works because *attackers can bruteforce easily + using steghide dictionary attacks*: once found the password is the + same for the steg crypto and the key crypto. + + Users should keep in mind these issues when planning their encryption + scheme and, when relying on steganography, keep the image always + mixed in the same folder with many more images since that will be the + multiplier making it slightly harder to bruteforce their password. + + In most cases consider that *password bruteforce is a feasible attack + vector on keys*. If there are doubts about a key being compromised is + a good practice to change it using the `setkey` command on a secure + machine, possibly while off-line or in single user mode. + # Versioning and stdin key ## 1.5