CVE-2025-8671-vulnerability-POC-

CVE-2025-8671 vulnerability POC

CVE-2025-8671 Vulnerability Scanner

A professional security research tool for detecting the MadeYouReset vulnerability (CVE-2025-8671) in HTTP/2 servers. This scanner uses multiple detection heuristics to identify servers vulnerable to stream accounting manipulation attacks.

🔍 About CVE-2025-8671

The MadeYouReset vulnerability exploits HTTP/2 stream accounting by forcing servers to send RST_STREAM frames via malformed protocol violations while backend processing continues. This creates a resource exhaustion condition that can lead to:

• Denial of Service (DoS) - Server resource exhaustion
• Backend overload - Processing continues despite stream resets
• Service degradation - Increased latency and 5xx errors

Attack Mechanism

The scanner tests three primary attack primitives:

1. WINDOW_UPDATE with increment=0 - Protocol violation per RFC 7540
2. WINDOW_UPDATE overflow - Flow control window overflow
3. DATA on half-closed stream - Sending data after END_STREAM

✨ Features

• ✅ Multi-indicator detection - Analyzes 7+ vulnerability signals
• ✅ Low false positives - Scoring system with confidence levels
• ✅ Batch scanning - Test multiple domains from a file
• ✅ Iterative testing - Multiple test runs for accuracy
• ✅ Detailed reporting - Verbose mode with real-time analysis
• ✅ Color-coded output - Easy-to-read terminal results

📋 Requirements

• Python 3.7+
• h2 library (hyper-h2)

🚀 Installation

1. Clone the Repository

git clone https://github.com/mysara2022/CVE-2025-8671-vulnerability-POC-.git
cd CVE-2025-8671-vulnerability-POC

2. Install Dependencies

pip3 install -r requirements.txt

Or install manually:

pip3 install h2

3. Make Scanner Executable

chmod +x cve-2025-8671-scanner.py---

## 📝 Domain List Format

Create a `domains.txt` file with one domain per line:

```text
# Production servers
prod-api.example.com
prod-web.example.com

# Staging servers
staging.example.org

# CDN endpoints
cdn1.example.net
cdn2.example.net

• Lines starting with # are treated as comments
• Empty lines are ignored---

📝 Domain List Format

Create a domains.txt file with one domain per line:

# Production servers
prod-api.example.com
prod-web.example.com

# Staging servers
staging.example.org

# CDN endpoints
cdn1.example.net
cdn2.example.net

• Lines starting with # are treated as comments
• Empty lines are ignored---

💻 Usage

Basic Usage

Test a single domain:

python3 cve-2025-8671-scanner.py example.com

Test multiple domains from a file:

python3 cve-2025-8671-scanner.py domains.txt

Advanced Options

python3 cve-2025-8671-scanner.py <domain|file> [options]

Options:
  --verbose    Show detailed testing output
  --runs N     Number of test iterations (default: 3)

Examples

Verbose single domain scan:

python3 cve-2025-8671-scanner.py vulnerable-server.com --verbose

Batch scan with 5 iterations:

python3 cve-2025-8671-scanner.py domains.txt --runs 5

Detailed analysis with verbose output:

python3 cve-2025-8671-scanner.py target.example.org --verbose --runs 5

• No http:// or https:// prefix needed

📊 Output Interpretation

Vulnerability Scores

The scanner calculates a vulnerability score (0-15+) based on multiple indicators:

Detection Indicators

The scanner analyzes these vulnerability signals:

1. Server RST_STREAM count - Server sending stream resets (key indicator)
2. HTTP 5xx errors - Backend overload symptoms
3. Latency increase - Performance degradation during attack
4. No GOAWAY received - Server doesn't detect abuse
5. Sustained impact - Consistent degradation across measurements
6. Backend mismatch - Processing continues after RST
7. Control frame tolerance - Server accepts malformed frames

Example Output

======================================================================
Testing: vulnerable-api.example.com
======================================================================

✓ vulnerable-api.example.com - VULNERABLE
  Confidence: HIGH (score: 8.0/max: 9)
  Indicators: 7.3 avg server RST, 2.0 avg 5xx, no GOAWAY

======================================================================
SCAN SUMMARY
======================================================================

  Total tested: 5
  Vulnerable: 2
  Likely vulnerable: 1
  Possibly vulnerable: 0
  Not vulnerable: 2

🔧 Technical Details

Detection Methodology

1. Baseline Measurement

   • Establishes normal server RTT via PING frames
   • Measures 5 baseline samples for statistical validity

2. Attack Phase

   • Opens up to 100 HTTP/2 streams
   • Sends malformed frames to trigger protocol violations
   • Monitors server responses in real-time

3. Analysis Phase

   • Aggregates metrics across multiple test runs
   • Calculates vulnerability score from 7+ indicators
   • Provides confidence-based classification

Attack Primitives

# WINDOW_UPDATE with increment=0 (RFC 7540 violation)
USE_WINDOW_UPDATE_ZERO = True

# WINDOW_UPDATE causing flow control overflow
USE_WINDOW_OVERFLOW = True

# DATA frames on half-closed streams
USE_HALF_CLOSED_DATA = True

Configuration

Key parameters (adjustable in source code):

PORT = 443                   # Target port
TIMEOUT = 6                  # Connection timeout
TOTAL_STREAMS = 100          # Max streams to open
SCAN_TIME_LIMIT = 15         # Max scan duration (seconds)
BASELINE_PINGS = 5           # Baseline RTT measurements

⚠️ Disclaimer

FOR SECURITY RESEARCH AND AUTHORIZED TESTING ONLY

This tool is provided for legitimate security research and vulnerability assessment. Users must:

• ✅ Obtain explicit authorization before scanning any systems
• ✅ Comply with all applicable laws and regulations
• ✅ Follow responsible disclosure practices
• ❌ NOT use for malicious purposes or unauthorized access

The authors assume no liability for misuse or damage caused by this software.

🔗 References

• CVE-2025-8671: NVD Entry
• RFC 7540: HTTP/2 Specification
• hyper-h2: Python HTTP/2 Library

⚡ Stay secure and scan responsibly!