| Name |
XML Ping of the Death |
|
| Likelyhood of attack |
Typical severity |
| Low |
Medium |
|
| Summary |
An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target. |
| Prerequisites |
The target must receive and process XML transactions. |
| Execution Flow |
| Step |
Phase |
Description |
Techniques |
| 1 |
Explore |
[Survey the target] Using a browser or an automated tool, an attacker records all instance of web services to process XML requests. |
- Use an automated tool to record all instances of URLs to process XML requests.
- Use a browser to manually explore the website and analyze how the application processes XML requests.
|
| 2 |
Exploit |
[Launch a resource depletion attack] The attacker delivers a large number of small XML messages to the target URLs found in the explore phase at a sufficiently rapid rate. It causes denial of service to the target application. |
- Send a large number of crafted small XML messages to the target URL.
|
|
| Solutions | Design: Build throttling mechanism into the resource allocation. Provide for a timeout mechanism for allocated resources whose transaction does not complete within a specified interval. Implementation: Provide for network flow control and traffic shaping to control access to the resources. |
| Related Weaknesses |
|
CWE ID
|
Description
|
| CWE-400 |
Uncontrolled Resource Consumption |
| CWE-770 |
Allocation of Resources Without Limits or Throttling |
|
| Related CAPECS |
|
CAPEC ID
|
Description
|
| CAPEC-528 |
An adversary may execute a flooding attack using XML messages with the intent to deny legitimate users access to a web service. These attacks are accomplished by sending a large number of XML based requests and letting the service attempt to parse each one. In many cases this type of an attack will result in a XML Denial of Service (XDoS) due to an application becoming unstable, freezing, or crashing. XDoS is most closely associated with web services, SOAP, and Rest, because remote service requesters can post malicious XML payloads to the service provider designed to exhaust the service provider's memory, CPU, and/or disk space. The main weakness in XDoS is that the service provider generally must inspect, parse, and validate the XML messages to determine routing, workflow, security considerations, and so on. It is exactly these inspection, parsing, and validation routines that XDoS targets. This attack exploits the loosely coupled nature of web services, where the service provider has little to no control over the service requester and any messages the service requester sends. |
|