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Posts tagged #ctf

114 posts

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2025 Cyber Apocalypse: Crypto Traces

Exploit AES-CTR mode vulnerability in a custom IRC-like server with reused counter initialization

#htb #ctf #cryptography
+3
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2025 Cyber Apocalypse: Silent Trap

Analyze compromised system through network traffic and memory forensics to uncover malware deployment and credential theft

#htb #ctf #forensics
+4
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2025 Cyber Apocalypse: Stealth Invasion

Analyze memory dump of compromised Linux system to uncover malicious Chrome extension and credential theft

#htb #ctf #forensics
+4
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2025 Cyber Apocalypse: Arcane Auctions

Identify and exploit secure coding vulnerabilities in a web application

#htb #ctf #secure-coding
+2
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2025 Cyber Apocalypse: Web Cyber Attack

Exploit path traversal vulnerability in a PHP web application to extract the flag

#htb #ctf #web
+3
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2024 Hack The Boo: Ghostly Persistence

Analyze Windows event logs to uncover two-part flag hidden in PowerShell command execution and log artifacts

#htb #ctf #forensics
+3
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2024 Hack The Boo: TerrorFryer

Reverse engineer a binary that uses Fisher-Yates shuffling to find the original input string

#htb #ctf #reversing
+3
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2024 Hack The Boo: Practice

Reverse engineer encoded strings from JavaScript code to extract hidden data

#htb #ctf #forensics
+2
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2024 Hack The Boo: Cursed Stale Policy

Exploit stale cache policy vulnerabilities in a web application with Content Security Policy analysis

#htb #ctf #web
+3
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2024 Hack The Boo: Waywitch

Exploit JWT authentication bypass and token manipulation in a Node.js web application

#htb #ctf #web
+3
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2024 Business CTF - Vault of Hope: Recruitment

Smart contract challenge requiring multi-step validation including hacking skills, stealth, engineering, and demolition expertise

#htb #ctf #blockchain
+2
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2024 Business CTF - Vault of Hope: Exciting Outpost Recon

Cryptography challenge using known plaintext attack to break XOR-based encryption with SHA-256 key derivation

#htb #ctf #crypto
+3
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2024 Business CTF - Vault of Hope: Protrude

AWS IAM and cloud security challenge involving credential enumeration and permission analysis

#htb #ctf #cloud
+3
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2024 Business CTF - Vault of Hope: Scurried

AWS IAM role ARN extraction challenge using role ID to construct proper ARN format

#htb #ctf #cloud
+3
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2024 Business CTF - Vault of Hope: Submerged

Full penetration test of web server with SPIP CMS exploitation, leading to initial access and system compromise

#htb #ctf #fullpwn
+3
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2024 Business CTF - Vault of Hope: Caving

Windows forensics challenge analyzing PowerShell logs and obfuscated scripts to detect intrusion attempts

#htb #ctf #forensics
+3
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2024 Business CTF - Vault of Hope: Survivor

Full penetration test of Ubuntu web server with SSH and HTTP services

#htb #ctf #fullpwn
+2
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2024 Business CTF - Vault of Hope: Swarm

Full penetration test with multi-service enumeration including SSH and HTTP on multiple ports

#htb #ctf #fullpwn
+2
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2024 Business CTF - Vault of Hope: Sneak Peak

ICS/SCADA challenge involving Modbus protocol communication with industrial control systems

#htb #ctf #ics
+3
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2024 Business CTF - Vault of Hope: Rev FlagCasino

Binary reverse engineering challenge involving libc random number prediction and brute-force seed discovery

#htb #ctf #reversing
+3
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2024 Cyber Apocalypse: Dynasty

Reverse a custom Caesar cipher variant with position-dependent shift

#htb #ctf #crypto
+3
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2024 Cyber Apocalypse: Blunt

Exploit weak Diffie-Hellman with small parameters to recover shared secret and decrypt AES-CBC ciphertext

#htb #ctf #crypto
+3
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2024 Cyber Apocalypse: Russian Roulette

Exploit a weak Diffie-Hellman key exchange with small prime modulus

#htb #ctf #blockchain
+3
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2024 Cyber Apocalypse: Iced Tea

Identify TEA cipher from DELTA constant and decrypt ECB-mode ciphertext with known key

#htb #ctf #crypto
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2024 Cyber Apocalypse: Permuted

Break Diffie-Hellman over permutation groups using DLP algorithm on permutation cycles

#htb #ctf #crypto
+3
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2024 Cyber Apocalypse: Makeshift

Reverse a trivial string transformation: reverse flag then rearrange groups of three

#htb #ctf #crypto
+2
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2024 Cyber Apocalypse: Primary Knowledge

Exploit RSA implementation using prime modulus instead of semiprime

#htb #ctf #crypto
+2
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2024 Cyber Apocalypse: Data Siege

Exploit ActiveMQ vulnerability, extract .NET malware, decrypt C2 communications, and recover multi-part flag

#htb #ctf #forensics
+5
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2024 Cyber Apocalypse: Phreaky

Analyze PCAP to detect SMTP exfiltration and reconstruct PDF from parts

#htb #ctf #forensics
+4
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2024 Cyber Apocalypse: Confinement

Analyze disk image to extract and decrypt ransomware, then decrypt encrypted files

#htb #ctf #forensics
+4
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2024 Cyber Apocalypse: An Unusual Sighting

Extract flag from HTML content hidden in email file

#htb #ctf #forensics
+3
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2024 Cyber Apocalypse: Fake Boost

Extract obfuscated PowerShell from PCAP, deobfuscate, decrypt AES payload, and recover flag parts

#htb #ctf #forensics
+5
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2024 Cyber Apocalypse: Game Invitation

Analyze malicious DOCM file, extract XOR-encrypted payload, decrypt JavaScript layers, and recover C2 beacon

#htb #ctf #forensics
+5
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2024 Cyber Apocalypse: Oblique Final

Analyze memory dump with Volatility and extract artifacts from system state

#htb #ctf #forensics
+3
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2024 Cyber Apocalypse: Pursue The Tracks

Analyze MFT records to answer forensic questions about file activity

#htb #ctf #forensics
+4
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2024 Cyber Apocalypse: Urgent

Decode base64 email attachments and URL-decode payloads to uncover phishing attack details

#htb #ctf #forensics
+4
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2024 Cyber Apocalypse: Character

Automate character-by-character flag extraction from server using socket programming

#htb #ctf #misc
+3
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2024 Cyber Apocalypse: Hardware Rids

Interface with W25Q128 flash memory via SPI to read flag from device

#htb #ctf #hardware
+4
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2024 Cyber Apocalypse: Cubicle Riddle

Construct Python bytecode to find min/max values and answer the cube's riddle

#htb #ctf #misc
+3
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2024 Cyber Apocalypse: Stop Drop and Roll

Script game responses to survive The Fray video game challenge

#htb #ctf #misc
+3
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2024 Cyber Apocalypse: Unbreakable

Bypass blacklist filters in Python eval() to read the flag

#htb #ctf #misc
+3
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2024 Cyber Apocalypse: Delulu

Exploit format string vulnerability to overwrite target variable

#htb #ctf #pwn
+2
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2024 Cyber Apocalypse: Pwn Tutorial

Answer integer overflow questions to retrieve the flag

#htb #ctf #pwn
+2
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2024 Cyber Apocalypse: Writing on the Wall

Exploit off-by-one vulnerability and strcmp null byte behavior

#htb #ctf #pwn
+3
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2024 Cyber Apocalypse: BoxCutter

Use strace to identify file access attempts and retrieve the flag

#htb #ctf #reverse
+3
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2024 Cyber Apocalypse: Crushing

Reverse engineer a compression algorithm and decode serialized data

#htb #ctf #reverse
+3
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2024 Cyber Apocalypse: Testimonial

Exploit gRPC path traversal to overwrite application files

#htb #ctf #web
+3
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2024 Cyber Apocalypse: TimeKORP

Exploit command injection in time-based functionality

#htb #ctf #web
+2
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2024 Cyber Apocalypse: KorpTerminal

Exploit SQL injection to retrieve credentials and login

#htb #ctf #web
+2
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2024 Cyber Apocalypse: PackedAway

Unpack UPX-compressed executable to reveal hidden strings and flag

#htb #ctf #reverse
+3
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2024 Cyber Apocalypse: Labyrinth Linguist

Exploit Apache Velocity Server-Side Template Injection (SSTI)

#htb #ctf #web
+3
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2024 Cyber Apocalypse: LockTalk

Exploit JWT vulnerabilities in python-jwt version 3.3.3

#htb #ctf #web
+3
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2024 Cyber Apocalypse: SerialFlow

Exploit memcached injection and Python pickle deserialization for RCE

#htb #ctf #web
+4
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2024 Cyber Apocalypse: Web SerialFlow

Exploit serialization vulnerabilities to achieve RCE through pickle deserialization

#htb #ctf #web
+3
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HTB Hack The Boo Practice: Hexoding64

Decode a flag split between hex and base64 encoding

#htb #ctf #crypto
+3
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HTB Hack The Boo Practice: SPG

Reverse engineer a password generator to decrypt an encrypted flag

#htb #ctf #crypto
+3
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HTB Hack The Boo Practice: yesnce

Exploit AES-CTR mode with predictable counter and key recovery

#htb #ctf #crypto
+3
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HTB Hack The Boo Practice: Candyvault

NoSQL injection in login form to bypass authentication

#htb #ctf #web
+3
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HTB Hack The Boo Practice: Web Pumpkinspice

Command injection vulnerability in localhost-restricted endpoint

#htb #ctf #web
+3
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HTB Hack The Boo Practice: Web Spellbound Servants

Pickle deserialization exploitation for remote code execution

#htb #ctf #web
+4
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HTB Hack The Boo Practice: Web Spooktastic

XSS via filter bypass using noembed tag

#htb #ctf #web
+3
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HTB Hack The Boo Practice: Web Candyvault

NoSQL injection in authentication bypass with MongoDB

#htb #ctf #web
+3
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HTB Hack The Boo 2023: Rev Spellbrewery

.NET binary reverse engineering challenge

#htb #ctf #reverse-engineering
+2
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HTB Hack The Boo 2023: Web HauntMart

SSRF vulnerability leading to admin account creation

#htb #ctf #web
+3
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2023 Business CTF: 2244 Elections

Exploit a backdoored e-voting smart contract to manipulate election results

#htb #ctf #blockchain
+2
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2023 Business CTF: Confidentiality

Forge NFT signatures to gain access to confidential Board of Arodor documents

#htb #ctf #blockchain
+3
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2023 Business CTF: Contempt - Revenge

Full system compromise requiring exploitation chain through multiple vulnerabilities

#htb #ctf #fullpwn
+2
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2023 Business CTF: Funds Secured

Exploit a multi-signature wallet to steal crowdfunding campaign funds

#htb #ctf #blockchain
+3
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2023 Business CTF: Initialization

Break AES-CTR encryption with nonce reuse vulnerability

#htb #ctf #crypto
+3
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2023 Business CTF: Unveiled

Enumerate and exploit misconfigured AWS S3 buckets to access confidential information

#htb #ctf #cloud
+3
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2023 Business CTF: Interception

Exploit weak PRNG in RSA system to decrypt enemy communications

#htb #ctf #crypto
+3
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2023 Business CTF: Vitrium Stash

Forge DSA signatures to access vitalium resource coordinates

#htb #ctf #crypto
+3
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2023 Business CTF: Paid Contr-actor

Sign a contract with a simple condition to complete military enrollment paperwork

#htb #ctf #blockchain
+2
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2023 Business CTF: I'm gRoot

Forge Merkle tree signatures to detect a blockchain backdoor

#htb #ctf #crypto
+3
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2023 Business CTF: Lagmon

Exploit WordPress plugin vulnerabilities and LLM prompt injection for RCE

#htb #ctf #fullpwn
+4
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2023 Business CTF: Vanguard

Full exploitation of a web application with file upload vulnerability, command injection, and privilege escalation.

#htb #ctf #fullpwn
+4
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2023 Business CTF: Device Control

Exploit a device control server to manipulate devices or gain system access.

#htb #ctf #pwn
+3
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2023 Business CTF: PAC Breaker

Exploit a surveillance system tracking application by bypassing file restrictions and causing heap corruption.

#htb #ctf #pwn
+4
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2023 Business CTF: Hackback

Exploit a Command and Control (C2) service by exploiting vulnerabilities in its bot management system.

#htb #ctf #pwn
+4
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2023 Business CTF: Snow Scan

Bypass a bitmap scanning application by crafting a malicious BMP file to trigger code execution.

#htb #ctf #pwn
+4
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2023 Business CTF: Cobalt COBOL

Reverse engineer an ancient COBOL punch card program representing a facility update.

#htb #ctf #reverse-engineering
+3
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2023 Business CTF: Breach

Exploit a Modbus-based SCADA door control system by manipulating sensors and coils.

#htb #ctf #scada
+4
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2023 Business CTF: ICS Intrusion

Analyze captured Modbus network traffic to extract sensitive data from industrial control registers.

#htb #ctf #scada
+5
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2023 Business CTF: ICS Watch Tower

Analyze network captures to identify intruder reconnaissance and data tampering on industrial systems.

#htb #ctf #scada
+4
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2023 Business CTF: Web Watersnake

Exploit a Java deserialization vulnerability in a water level monitoring application.

#htb #ctf #web
+5
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2023 Cyber Apocalypse: Small sTeps

Exploit RSA with small public exponent e=3 using Coppersmith's attack

#htb #ctf #crypto
+3
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2023 Cyber Apocalypse: Multipage Recyclings

Exploit custom AES ECB implementation with block recycling vulnerability

#htb #ctf #crypto
+3
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2023 Cyber Apocalypse: Extraterrestrial Persistence

Analyze and decode malicious script with systemd persistence mechanism

#htb #ctf #forensics
+3
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2023 Cyber Apocalypse: Perfect Synchronization

Exploit AES ECB mode encryption with known plaintext and partial key recovery

#htb #ctf #crypto
+3
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2023 Cyber Apocalypse: Ancient Encodings

Reverse engineer a multi-layer encoding scheme involving hex conversion and base64

#htb #ctf #crypto
+3
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2023 Cyber Apocalypse: HW Debug

Hardware debugging and analysis of timing/electrical signals

#htb #ctf #hardware
+2
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2023 Cyber Apocalypse: Hijack

Exploit Python deserialization vulnerabilities in YAML and Pickle

#htb #ctf #misc
+4
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2023 Cyber Apocalypse: Janken

Win 100 rounds of Janken by exploiting logic in string matching

#htb #ctf #misc
+3
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2023 Cyber Apocalypse: Persistence

Automate repeated HTTP requests to extract flag from endpoint

#htb #ctf #misc
+3
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2023 Cyber Apocalypse: Nehebkaus Trap

Exploit Python exec() filter bypass using character encoding

#htb #ctf #misc
+3
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2023 Cyber Apocalypse: Remote Computation

Automate mathematical expression evaluation over TCP socket

#htb #ctf #misc
+3
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2023 Cyber Apocalypse: Restricted

Escape restricted SSH environment using bash profile bypass

#htb #ctf #misc
+3
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2023 Cyber Apocalypse: The Chasm Crossing Conundrum

Solve bridge crossing puzzle using optimal algorithm

#htb #ctf #misc
+3
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2023 Cyber Apocalypse: Questionnaire

Buffer overflow via fgets() vulnerability in vulnerable C binary

#htb #ctf #pwn
+3
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2023 Cyber Apocalypse: Getting Started

Buffer overflow exploitation using controlled payload delivery

#htb #ctf #pwn
+3
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2023 Cyber Apocalypse: CSHells

Reverse engineer custom shell binary and crack XOR-encrypted password

#htb #ctf #reverse
+3
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2023 Cyber Apocalypse: Cave System

Solve complex multi-condition logic puzzle in binary

#htb #ctf #reverse
+2
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2023 Cyber Apocalypse: Shattered Tablet

Reconstruct input string by analyzing multi-byte field access patterns

#htb #ctf #reverse
+2
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2023 Cyber Apocalypse: Orbital

Exploit SQL injection vulnerability and use path traversal to extract flag

#htb #ctf #web
+3
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2023 Cyber Apocalypse: Didactic Octo Paddle

Exploit IDOR and JWT vulnerabilities in shopping application

#htb #ctf #web
+3
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2023 Cyber Apocalypse: Hunting License

Crack three-stage password validation in binary using string reversal and XOR

#htb #ctf #reverse
+3
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2023 Cyber Apocalypse: Passman

Exploit IDOR vulnerability in GraphQL API to access admin data

#htb #ctf #web
+3
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2022 Hack The Boo: Gonna Lift Em All

Discrete log problem with extremely small prime - trivial brute force attack

#htb #ctf #crypto
+3
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2022 Hack The Boo: Whole Lotta Candy

AES encryption challenge with multiple block cipher modes - exploit ECB mode weakness

#htb #ctf #crypto
+4
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2022 Hack The Boo: Cursed Party

JWT authentication bypass through XSS to steal admin session and access flag

#htb #ctf #web
+5
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2022 Hack The Boo: Evaluation Deck

Code injection via unsafe use of Python compile() and exec() in arithmetic evaluation

#htb #ctf #web
+5
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2022 Hack The Boo: Horror Feeds

SQL injection in user registration leading to authentication bypass and flag theft

#htb #ctf #web
+4
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2022 Hack The Boo: Juggling Facts

IP spoofing via X-Forwarded-For header to bypass localhost-only admin access

#htb #ctf #web
+4
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2022 Hack The Boo: Spookifier

Server-Side Template Injection (SSTI) in Mako template engine leading to RCE

#htb #ctf #web
+5