ctf-flag-verification

Extract and validate CTF flags for format, encoding, and length.

1.6k|234|Updated Dec 7, 2019

Search Tags:#validation #verification #encoding #ctf #submission #flag

Ready to run

npx skills add https://github.com/wgpsec/AboutSecurity --skill ctf-flag-verification

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: ctf-flag-verification
Source: https://github.com/wgpsec/AboutSecurity/tree/main/skills/ctf/ctf-flag-verification
Command: npx skills add https://github.com/wgpsec/AboutSecurity --skill ctf-flag-verification

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

CTF teams often struggle with unreliable flag extraction and submission due to encoding issues, truncation, and hidden characters.

Core Features & Use Cases

Automated flag extraction across diverse formats and sources.
Comprehensive validation for length, format, and decoding to prevent incorrect submissions.
Guided workflow to apply verification before submitting flags in web, binary, and puzzle challenges.

Quick Start

Provide a suspected flag string to the AI and have it verify formatting, encoding, and length before submission.

Frequently Asked Questions about ctf-flag-verification

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I verify a CTF flag format and encoding before submission?▼

CTF flag verification involves checking the suspected flag string against expected formats, lengths, and decoding requirements. This workflow prevents incorrect submissions by identifying hidden characters, truncation, and encoding issues before you submit.

Why does my extracted flag fail CTF submission even when it looks correct?▼

Extracted flags often fail CTF submission due to hidden characters, truncation, or encoding issues. Applying a rigorous verification workflow identifies these invisible formatting problems and enforces proper decoding before the submission attempt.

Can I extract and validate flags from SQL injection or command execution outputs?▼

Yes, automated flag extraction supports common scenarios including SQL injection, command execution, local file reading, and HTML or JavaScript embedded flags. It validates the extracted string against expected constraints before you submit.

What is the best way to handle flag assembly and validation for puzzle challenges?▼

The best way to handle flag assembly is using a guided workflow that applies programmatic validation with guardrails. This enforces expected length, format, and decoding constraints, ensuring the assembled flag meets submission requirements.

How do I check for hidden characters or truncation in a suspected flag string?▼

To check for hidden characters and truncation in a suspected flag string, provide the string to an automated verification workflow. It rigorously inspects the encoding and applies length constraints to catch invisible formatting errors.