| Name |
AJAX Footprinting |
|
| Likelyhood of attack |
Typical severity |
| High |
Low |
|
| Summary |
This attack utilizes the frequent client-server roundtrips in Ajax conversation to scan a system. While Ajax does not open up new vulnerabilities per se, it does optimize them from an attacker point of view. A common first step for an attacker is to footprint the target environment to understand what attacks will work. Since footprinting relies on enumeration, the conversational pattern of rapid, multiple requests and responses that are typical in Ajax applications enable an attacker to look for many vulnerabilities, well-known ports, network locations and so on. The knowledge gained through Ajax fingerprinting can be used to support other attacks, such as XSS. |
| Prerequisites |
The user must allow JavaScript to execute in their browser |
| Execution Flow |
| Step |
Phase |
Description |
Techniques |
| 1 |
Explore |
[Send request to target webpage and analyze HTML] Using a browser or an automated tool, an adversary sends requests to a webpage and records the received HTML response. Adversaries then analyze the HTML to identify any known underlying JavaScript architectures. This can aid in mappiong publicly known vulnerabilities to the webpage and can also helpo the adversary guess application architecture and the inner workings of a system. |
- Record all "src" values inside script tags. These JavaScript files are compared to lists of files for known architectures. If there is a large match between the "src" values and architecture files, then it can be assumed that particular architecture is being used.
|
|
| Solutions | Design: Use browser technologies that do not allow client side scripting. Implementation: Perform input validation for all remote content. |
| Related Weaknesses |
|
CWE ID
|
Description
|
| CWE-20 |
Improper Input Validation |
| CWE-79 |
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') |
| CWE-86 |
Improper Neutralization of Invalid Characters in Identifiers in Web Pages |
| CWE-96 |
Improper Neutralization of Directives in Statically Saved Code ('Static Code Injection') |
| CWE-113 |
Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting') |
| CWE-116 |
Improper Encoding or Escaping of Output |
| CWE-184 |
Incomplete List of Disallowed Inputs |
| CWE-348 |
Use of Less Trusted Source |
| CWE-692 |
Incomplete Denylist to Cross-Site Scripting |
|
| Related CAPECS |
|
CAPEC ID
|
Description
|
| CAPEC-63 |
An adversary embeds malicious scripts in content that will be served to web browsers. The goal of the attack is for the target software, the client-side browser, to execute the script with the users' privilege level. An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute code and scripts. Web browsers, for example, have some simple security controls in place, but if a remote attacker is allowed to execute scripts (through injecting them in to user-generated content like bulletin boards) then these controls may be bypassed. Further, these attacks are very difficult for an end user to detect. |
| CAPEC-580 |
An adversary engages in active probing and exploration activities to determine security information about a remote target system. Often times adversaries will rely on remote applications that can be probed for system configurations. |
|