14
Tmto pdf cracker

Tmto pdf cracker

Embed Size (px)

Citation preview

Tmto pdf cracker

What is PDF

• Portable document format• Open standard for documentation• By adobe systems in 1993• Complete description of fixed layout flat

document, text graphics ,fonts and other information

• Was proprietary then became official in 2008

File structure

• 8 tyes of object– Boolean– Strings arrays– Names– Dictionaries – Streams

Encryption

• What to encryption • What to encrypt• Types of encryption

Current techniques

• Bruteforce – Trying each and every possible combination of

character set

• Dictionary– Making list most possible list of password and

trying them.

Problems with current technique

• It takes days to recover password• Resources needed to recover password are

much more • Computation required are more

New concept

• TIME MEMORY TRADE OFF– What is it?– Why

Benefits of TMTO

• Less time to recover password• Less computation required

Problems with TMTO

• Hash collision • Huge disk space

Solution to problems

• Collusion avoidance technique– Chaining

• Smart hashing– Similar to dictionary attack

Internal Modules for recovery utility

Internal modules for RB Generation

Advantages & Disadvantages

Future Development