Linux Exploitation Expert

Linux Exploitation Expert — HackTricks Training

Progress from binary exploitation fundamentals to advanced exploit development in Linux across user space, heap, ARM, kernel, and browser targets.

View Course

CTF categories

Highlighted writeups

Infinite Knapsack
CTF

Infinite Knapsack

Knapsack. Brute force. Modular arithmetic. Shuffling. LLL lattice reduction
BatchCraft Potions
CTF

BatchCraft Potions

GraphQL batching attack. OTP and rate limit bypass. JWT. CSP. DOM Clobbering. XSS
Vitrium Stash
CTF

Vitrium Stash

DSA. Modular arithmetic. LLL lattice reduction
Share
CTF

Share

HITCON CTF Quals 2023. Shamir Secret Sharing. Lagrange interpolation. Chinese Remainder Theorem. multiprocessing
Clutch
CTF

Clutch

HTB UniCTF 2024. Quantum Cryptography. Frame-based Quantum Key Distribution
FileStorage
CTF

FileStorage

64-bit binary. Buffer Overflow. Format String vulnerability. FILE structure attack. GOT overwrite
More

Recent CTF

Hubbub
CTF

Hubbub

Arduino reversing. Morse code
quick maffs
CTF

quick maffs

RSA. Low Exponent and Related Messages attack. Groebner basis. Brute force
Lost Modulus Again
CTF

Lost Modulus Again

RSA. Greatest Common Divisor. Franklin-Reiter related-message attack. Coppersmith’s short-pad attack
BinCrypt Breaker
CTF

BinCrypt Breaker

Reversing encryption algorithm. XOR cipher
CDNio
CTF

CDNio

Cache poisoning
More CTF

Recent HTB

Facts
HTB

Facts

Hack The Box. Linux. Easy machine. This machine has an outdated version of Camaleon CMS that is vulnerable to Local File Read. With this vulnerability we can read the private SSH key of a user, crack the passphrase and access the machine. Then, this user has sudo permissions to run command facter as root, which can be used to escalate privileges using a Ruby script
Interpreter
HTB

Interpreter

Hack The Box. Linux. Medium machine. This machine has a Mirth Connect instance that is vulnerable to Unauthenticated Remote Code Execution. After getting a reverse shell, we can find a database credentials and a hashed password inside. We must analyze how the hash is generated in order to crack it. Once we have the password, we can access via SSH and find out an internal webserver running as root that has a code injection vullnerability in Python due to eval and f-strings, which allows us to escalate to root
Eighteen
HTB

Eighteen

Hack The Box. Windows. Easy machine. In this assumed-breach machine we have credentials for an exposed MSSQL service where we can impersonate another user and find a hashed password for the website hosted by the machine. This hash can be cracked to find a password. After enumerating users by brute forcing RIDs in MSSQL, we find that it is reused by a domain user and we get access via WinRM. There is a bad ACL configured to group IT and we can use BadSuccessor to escalate privileges, after configuring a SOCKS proxy to access required AD services
Dog
HTB

Dog

Hack The Box. Linux. Easy machine. This machine hosts a CMS that exposes a Git repository. Once we dump the repository, we can find a username and a database password that can be reused to log in as administrator of the CMS. Here, we can install a new module to execute a PHP web shell and get a reverse shell on the machine. Although there are hashed passwords on the database, the same password can be reused for a system user. Finally, we are allowed to run bee as root using sudo, which will let us escalate privileges by running arbitrary PHP code
Titanic
HTB

Titanic

Hack The Box. Linux. Easy machine. This machine has a Local File Read vulnerability where we can read sensitive files. There is a Gitea instance with some repositories and a Docker configuration that shows how Gitea files are shared in a volume mount. So, we can find hashed passwords on the Gitea SQLite database and crack them. With this, we gain access via SSH reusing credentials. After that, we find a script running as root using a vulnerable version of ImageMagick where we can perform a library hijacking to get arbitrary code execution, as root
More HTB

Recent IMC

IMC

IMC 2021, Problem 1

Let be a real matrix such that .
  1. Prove that there is a unique real matrix that satisfies the equation
  2. Express in terms of .
IMC

IMC 2020, Problem 5

Find all twice continuously differentiable functions satisfying for all .
IMC

IMC 2020, Problem 2

Let and be real matrices such that where is the identity matrix. Prove that
IMC

IMC 2020, Problem 1

Let be a positive integer. Compute the number of words (finite sequences of letters) that satisfy the following three properties:
  1. consists of letters, all of them are from the alphabet .
  2. contains an even number of letters .
  3. contains an even number of letters .
(For example, for , there are 6 such words: , , , , and )
More IMC