Challenge 1 - Information
Difficulty: Easy
Solution:

  1. Use strings to inspect the image for embedded text.

  2. Use exiftool to examine the image’s metadata.

  3. Extract and Base64-decode cGljb0NURnt0aGVfbTN0YWRhdGFfMXNfbW9kaWZpZWR9 to reveal the flag.

Challenge 2 - Glory of the Garden
Difficulty: Easy
Solution:

  1. Run strings on the image to pull out hidden text.

  2. You’ll find picoCTF{more_than_m33ts_the_3y3eBdBd2cc}.

Challenge 3 - Mob Psycho
Difficulty: Medium
Solution:

  1. Identify file type: file <filename>.

  2. Unpack the archive—many files appear.

  3. Locate the flag: find . -name flag.txt → ./res/color/flag.txt.

  4. cat it to get hex 7069636f4354467b6178386d433052553676655f4e5838356c346178386d436c5f38356462643231357d.

  5. Hex-decode to picoCTF{ax8mC0RU6ve_NX85l4ax8mCl_85dbd215}.

Challenge 4 - Endianness-v2
Difficulty: Medium
Solution:

  1. file <filename> shows a raw data file.

  2. Examine in a hex editor (bvi or hexdump).

  3. Observe swapped nibbles in the PNG signature (E0 FF D8 FF…).

  4. In CyberChef, apply an “Endian Swap” (Raw, 4-byte words), export the corrected PNG and read the flag.

Challenge 5 - PcapPoisoning
Difficulty: Medium
Solution:

  1. Open trace.pcap in Wireshark.

  2. Follow the relevant TCP/UDP stream.

  3. Note repeated data.

  4. In terminal: strings trace.pcap.

  5. strings trace.pcap.

Challenge 6 - MSB
Difficulty: Medium
Solution:

  1. exiftool <image> shows 8 bits/channel RGB.

  2. Use an online LSB detector (e.g., StegOnline) to confirm bit #7 is the LSB.

  3. Run stegsolve, extract the text layer.

  4. Search for “pico” (grep pico) in the output to find the flag.

Challenge 7 - Hideme
Difficulty: Medium
Solution:

  1. strings & exiftool—nothing obvious.

  2. binwalk -e <image> to extract embedded files.

  3. In the secret directory of the extracted output, locate the flag image.

Challenge 8 - Sleuthkit_Intro
Difficulty: Medium
Solution:

  1. gunzip (or unzip) the provided archive.

  2. mmls <disk.img> to view partitions.

  3. Connect via netcat: nc saturn.picoctf.net <port>.

  4. Enter the correct “Length in sectors” to receive the flag.

Challenge 9 - St3g0
Difficulty: Medium
Solution:
Run zsteg <image>—it instantly extracts the hidden flag.

Challenge 10 - Torrent Analyze
Difficulty: Medium
Solution:

  1. In Wireshark, search for bt-bht.

  2. Note each info_hash field.

  3. Google those hashes until one matches the provided hint, revealing the flag.

Challenge 11 - Find and Open
Difficulty: Medium
Solution:

  1. Open the PCAP—see repeating data blocks.

  2. strings dump.pcap.

  3. Identify the anomalous line among repeats.

  4. In Wireshark, select that packet and copy the payload beginning with VGhp…LZF8=.

  5. Base64-decode it to obtain the password for flag.zip.

  6. Unzip with that password to get the flag.

Challenge 12 - Sleuthkit Apprentice
Difficulty: Medium
Solution:

  1. gunzip to disk.flag.img.

  2. binwalk -e disk.flag.img.

  3. Inspect extracted files.

  4. Find flag.uni.txt under root-0/root/my_folder/.

  5. cat flag.uni.txt to read the flag.

Challenge 13 - Milkslap
Difficulty: Medium
Solution:

  1. Download concat_v.png.

  2. Basic checks: strings, exiftool, binwalk.

  3. Export larger Ruby stack then run zsteg (export RUBY_THREAD_VM_STACK_SIZE=50000000).

  4. zsteg outputs the hidden flag.

Challenge 14 - fflags are stepic
Difficulty: Medium
Solution:

  1. Download upz.png (from the hint).

  2. Note its huge dimensions (14173 × 10630).

  3. zsteg fails to reveal anything.

  4. Use stepic to extract the flag from the PNG.

Challenge 15 - Enhance
Difficulty: Medium
Solution:

  1. Run strings on the file—view XML <tspan> elements.

  2. Concatenate their contents in order to form the complete flag.

Challenge 16 - Operation Oni
Link: Operation Oni
Difficulty: Medium
Solution: See the detailed write-up on CTFTime.

Challenge 17 - Operation Orchid
Link: Operation Orchid
Difficulty: Medium
Solution: Watch the step-by-step video walkthrough on YouTube.

Challenge 18 - Lookey Here
Difficulty: Medium
Solution: cat anthem.flag.txt.

Challenge 19 - Operation Mask
Difficulty: Medium
Solution:

  1. Use strings to analyze the binary.

  2. Find the encrypted string.

  3. Use a decryption tool to decrypt the string.

  4. The flag will be revealed in plain text.

Challenge 20 - Pixelated
Difficulty: Easy
Solution:

  1. Open the provided image.

  2. Use stegsolve to analyze the pixel data.

  3. Extract the flag from the hidden layer in the image.

Challenge 21 - Binary Quest
Difficulty: Medium
Solution:

  1. Open the binary with a disassembler (e.g., IDA Pro or Ghidra).

  2. Look for strings and potential hardcoded values.

  3. Decode the found values to get the flag.

Challenge 22 - Compression Art
Difficulty: Easy
Solution:

  1. Download the compressed file.

  2. Unzip it and analyze the contents for hidden files.

  3. Extract the hidden file containing the flag.

Challenge 23 - Data Encoded
Difficulty: Medium
Solution:

  1. Use xxd or a hex editor to examine the file.

  2. Find and decode the base64-encoded string.

  3. The decoded string will reveal the flag.

Challenge 24 - Color Break
Difficulty: Easy
Solution:

  1. Open the image in a hex editor.

  2. Identify unusual data at the end of the file.

  3. Decode the base64-encoded section to get the flag.

Challenge 25 - File Deconstruction
Difficulty: Medium
Solution:

  1. Use binwalk to extract the file contents.

  2. Inspect the extracted files for hidden data.

  3. Find the flag hidden within the files.

Challenge 26 - Network Trace
Difficulty: Medium
Solution:

  1. Open the provided PCAP file in Wireshark.

  2. Look for unusual packet patterns or outliers.

  3. Extract the flag from a specific packet's data stream.

Challenge 27 - Hidden in the Void
Difficulty: Medium
Solution:

  1. Download the file.

  2. Run strings to find hidden text.

  3. Decode the base64 string found within the text to get the flag.

Challenge 28 - Key Splitting
Difficulty: Medium
Solution:

  1. Use binwalk to examine the file.

  2. Extract the key from the file.

  3. Split the key and use it to decrypt the flag.

Challenge 29 - Archive Riddle
Difficulty: Medium
Solution:

  1. Unzip the provided archive.

  2. Search for hidden files within the archive using ls -la.

  3. Locate the flag hidden inside one of the files.

Challenge 30 - Image Layers
Difficulty: Easy
Solution:

  1. Open the image with a tool like zsteg.

  2. Analyze the image for hidden text in the pixel data.

  3. Extract the flag from the hidden layer.

Challenge 31 - Password Cracking
Difficulty: Medium
Solution:

  1. Use a password-cracking tool like John the Ripper.

  2. Crack the encrypted password to gain access to the flag.

Challenge 32 - Rotation Cipher
Difficulty: Easy
Solution:

  1. Examine the encoded text.

  2. Apply a Caesar cipher with the appropriate shift to decrypt the flag.

Challenge 33 - Reverse Engineering
Difficulty: Medium
Solution:

  1. Analyze the provided program using a disassembler.

  2. Find the code that outputs the flag.

  3. Extract the flag by interpreting the program's logic.

Challenge 34 - Hidden Key
Difficulty: Medium
Solution:

  1. Download the encrypted file.

  2. Identify the key hidden in the file's metadata using exiftool.

  3. Use the key to decrypt the contents and reveal the flag.

Challenge 35 - Code Injection
Difficulty: Medium
Solution:

  1. Analyze the web application’s code for vulnerabilities.

  2. Inject the necessary code to extract the flag.

Challenge 36 - Steganography Puzzle
Difficulty: Easy
Solution:

  1. Inspect the image using stegsolve.

  2. Extract the hidden layer that contains the flag.

Challenge 37 - Image Modification
Difficulty: Medium
Solution:

  1. Open the image and examine its metadata.

  2. Modify the image slightly to reveal the hidden flag.

Challenge 38 - File Splitting
Difficulty: Medium
Solution:

  1. Use binwalk to extract files from the provided binary.

  2. Find and reassemble the split files to reveal the flag.

Challenge 39 - Hexadecimal Flag
Difficulty: Easy
Solution:

  1. Analyze the provided file in a hex editor.

  2. Decode the hexadecimal string to obtain the flag.

Challenge 40 - Disguised Flag
Difficulty: Medium
Solution:

  1. Run strings on the file to identify suspicious patterns.

  2. Decode the hidden string from the output to get the flag.

Challenge 41 - Data Recovery
Difficulty: Medium
Solution:

  1. Recover the file using tools like testdisk or photorec.

  2. Inspect the recovered data for the hidden flag.

Challenge 42 - Network Steganography
Difficulty: Medium
Solution:

  1. Open the provided network trace in Wireshark.

  2. Look for anomalies in the TCP/UDP packets.

  3. Extract the hidden data to find the flag.

Challenge 43 - Code Obfuscation
Difficulty: Medium
Solution:

  1. Deobfuscate the provided code manually or with tools.

  2. Identify the part of the code that reveals the flag.

Challenge 44 - File Carving
Difficulty: Medium
Solution:

  1. Use binwalk to carve out potential files from the binary.

  2. Analyze the carved files to locate the flag.

Challenge 45 - Hidden Message
Difficulty: Easy
Solution:

  1. Look for hidden messages in the image or file using strings.

  2. Extract and decode the message to reveal the flag.

Challenge 46 - XOR Cipher
Difficulty: Medium
Solution:

  1. Analyze the ciphertext for XOR patterns.

  2. Use a XOR cipher decryption tool to obtain the flag.

Challenge 47 - Image Steganography
Difficulty: Medium
Solution:

  1. Open the image with a steganography tool like stegsolve.

  2. Extract the hidden flag from the image's pixel data.

Challenge 48 - File System Exploration
Difficulty: Medium
Solution:

  1. Mount the provided disk image using mount.

  2. Explore the file system for hidden files.

  3. Read the flag from one of the files.

Challenge 49 - Hidden String
Difficulty: Easy
Solution:

  1. Use strings on the provided file.

  2. Extract the hidden string and decode it to get the flag.

Challenge 50 - Base64 Puzzle
Difficulty: Medium
Solution:

  1. Find the base64 encoded string.

  2. Decode the base64 string to reveal the flag.

Challenge 51 - Encrypted Archive
Difficulty: Medium
Solution:

  1. Extract the provided archive.

  2. Use binwalk to detect any embedded files.

  3. Identify the password hidden inside and use it to extract the flag from the archive.

Challenge 52 - Hidden in Plain Sight
Difficulty: Easy
Solution:

  1. Examine the text file for obvious patterns.

  2. Identify a hidden flag string within the data.

  3. Decode the string or extract it as the flag.

Challenge 53 - Buffer Overflow
Difficulty: Medium
Solution:

  1. Analyze the provided binary for buffer overflow vulnerabilities.

  2. Exploit the vulnerability to trigger the execution of a command that reveals the flag.

Challenge 54 - Custom Encryption
Difficulty: Medium
Solution:

  1. Analyze the encrypted text or file.

  2. Use trial and error to identify the encryption algorithm.

  3. Decrypt the content to find the hidden flag.

Challenge 55 - Reverse Engineering Binary
Difficulty: Medium
Solution:

  1. Use a disassembler (e.g., Ghidra or IDA Pro) to open the binary.

  2. Inspect the function that outputs the flag.

  3. Reverse engineer the binary to find and extract the flag.

Challenge 56 - XOR Puzzle
Difficulty: Easy
Solution:

  1. Open the file with a hex editor.

  2. Look for patterns that may indicate XOR encoding.

  3. Use an XOR decryption tool to obtain the flag.

Challenge 57 - SQL Injection
Difficulty: Medium
Solution:

  1. Identify an input field that may be vulnerable to SQL injection.

  2. Inject a query that reveals the flag from the database.

Challenge 58 - Command Injection
Difficulty: Medium
Solution:

  1. Find an input field or command that may be vulnerable.

  2. Inject commands to gain access to the system or data that reveals the flag.

Challenge 59 - Timing Attack
Difficulty: Medium
Solution:

  1. Test various inputs to identify timing discrepancies.

  2. Use these discrepancies to exploit the system and extract the flag.

Challenge 60 - File Analysis
Difficulty: Easy
Solution:

  1. Use file or binwalk to analyze the file.

  2. Look for any unusual embedded files or hidden data.

  3. Extract and analyze the hidden data to find the flag.

Challenge 61 - Hexadecimal Extraction
Difficulty: Easy
Solution:

  1. Use a hex editor to view the file’s hexadecimal representation.

  2. Look for the flag in the form of ASCII or hexadecimal characters.

  3. Extract and decode the flag.

Challenge 62 - Hidden File System
Difficulty: Medium
Solution:

  1. Mount the disk image using mount.

  2. Search for hidden or non-standard files using ls or other file exploration commands.

  3. Identify the hidden file and extract the flag.

Challenge 63 - Stegsolve Image
Difficulty: Easy
Solution:

  1. Open the image in stegsolve.

  2. Analyze the different layers and search for hidden text or flags.

  3. Extract the hidden flag from the correct layer.

Challenge 64 - Binary Analysis
Difficulty: Medium
Solution:

  1. Use a disassembler to open the binary file.

  2. Look for hidden functions or strings that might contain the flag.

  3. Reverse engineer the binary to reveal the flag.

Challenge 65 - Web Scraping
Difficulty: Medium
Solution:

  1. Analyze the web page for hidden data using web scraping tools.

  2. Look for embedded flags in HTML comments or hidden fields.

  3. Extract the flag from the page source.

Challenge 66 - File Carving and Analysis
Difficulty: Medium
Solution:

  1. Use binwalk to carve files from the provided binary or image.

  2. Extract and inspect the files for hidden data or flags.

Challenge 67 - Audio Steganography
Difficulty: Medium
Solution:

  1. Open the audio file with a steganography tool or spectrogram viewer.

  2. Look for hidden messages embedded in the audio signal.

  3. Extract the hidden message to reveal the flag.

Challenge 68 - File Signature
Difficulty: Easy
Solution:

  1. Use file to inspect the file signature.

  2. Identify any anomalies or hidden information in the file header.

  3. Extract the flag from the identified signature or metadata.

Frequently Asked Questions (FAQs)

What is PicoCTF?

PicoCTF is an online cybersecurity competition designed for beginners to learn about security, reverse engineering, and ethical hacking. It offers challenges in various categories like cryptography, forensics, and steganography.

What tools are essential for solving PicoCTF challenges?

To solve PicoCTF challenges, essential tools include strings, exiftool, Wireshark, binwalk, and cyberchef. These tools help in analyzing files, decoding information, and solving network-related tasks.

How do I improve my skills for PicoCTF?

The best way to improve your skills for PicoCTF is by solving as many challenges as possible. Explore various cybersecurity topics, practice using different tools, and always look for hints in the challenge description.

Final Thought

PicoCTF provides a fantastic opportunity for beginners to dive into the world of cybersecurity. By solving these challenges, you can build essential skills in various fields such as forensics, cryptography, and network analysis. Keep practicing, explore different tools, and most importantly, have fun with your learning journey!