Some crypto-related scripts
Useful to solve some challenges or quick tests

This script check if a given RSA modulus has been factorised, using factordb.com (thanks to https://github.com/ryosan-470/factordb-pycli )
Handle PEM or DER encoded RSA public keys (-pubkey)
Can retrieve a TLS certificate and check the modulus if it uses RSA (-hostname ; it performs a certificate validation first)
ex : ./hibf.py -v -hostname github.com ; ./hibf.py -v -pubkey mypubkey.pem

This is an application of the chinese remainder theorem. Works directly with integers (--integers) or with RSA (--files)
input modulos as an array of integers or pubkey files (-n)
input congurences as an array of integers or base64 encoded data (-c)
As you know, this theorem can help you to recover a plaintext encrypted with RSA (under certain conditions, such as : e is small, all modulos must be pairwise coprimes, messages were encrypted with the same public exponent...)

ex : ./fcwl.py --integers -c 3 4 5 -n 17 11 6 ; this solves the following system :
x ≅ 3[7] ; x ≅ 4[11] ; x ≅ 5[6] Solution will be of the form : x ≅ K[17*11*6]

ex with RSA : ./fcwl.py --files -c enc_message1.txt enc_message2.txt encmessage3.txt -n pubkey1.pem pubkey2.pem pubkey3.pem
Assuming enc_messagei.txt was encrypted with pubkeyi.pem (so order matters). This will work if e << ∏(modulus) and try to print out the original message in plaintext

An application of Coppersmith's attack for stereotyped messages using SageMath (v9).
This theroem is based on LLL basis reduction algorithm and can be used when stereotyped messages (e.g. : logs) are encrypted using raw-RSA encryption scheme (e.g. without any padding system)

Like most of attacks deriving from Coppersmith's theorem, a low public exponent E is very helpful (since LLL algorithm tries to find roots of a polynomial of degree E at most)
Further conditions are also mandatory : size of the unknown part of the message must be smaller than N^(1/e)
If you are not sure about how long your unknown part is, you can easily tweak this script to test various size (i.e. adding some "*")

ex : sage copper_stereo.sage -n 120279682020498722984378664929957269995938437640582887988946285242233892284417856793385609226397118311238116720585802476226490347446060038688325286339720009935596353781452405089788532241908988880482772050730726814381672275409427764206380766693159708551111271803383167352452802991608314812878134420560882676109 -e 3 -c 38136682505766039559183446229674917251753001810843406283848627410563692534650927547349056899583207362946357233967856736264217071042350719553284683863158441231442974425888716015558761605868349441999675449974223613135532782350921534207873944341657719329194849592044365732569768296828022226690098363220197110347 -m "Your password is ******** and you should change it"