CAPEC-170 - Web Application Fingerprinting
An attacker sends a series of probes to a web application in order to elicit version-dependent and type-dependent behavior that assists in identifying the target. An attacker could learn information such as software versions, error pages, and response headers, variations in implementations of the HTTP protocol, directory structures, and other similar information about the targeted service. This information can then be used by an attacker to formulate a targeted attack plan. While web application fingerprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
Severity
Likelihood
Confidentiality
Integrity
Availability
- Attack Methods 1
- Analysis
- Purposes 1
- Reconnaissance
- Scopes 1
- "Varies by context"
- Confidentiality
Low level: Attacker knows how to send HTTP request, SQL query to a web application.
Any web application can be fingerprinted. However, some configuration choices can limit the useful information an attacker may collect during a fingerprinting attack.
While simple fingerprinting can be accomplished with only a web browser, for more thorough fingerprinting an attacker requires a variety of tools to collect information about the target. These tools might include protocol analyzers, web-site crawlers, and fuzzing tools. Footprinting a service adequately may also take a few days if the attacker wishes the footprinting attempt to go undetected.
Step 1 - Request fingerprinting
Use automated tools or send web server specific commands to web server and wait for server's response..
Tecnique ID: 1 - Environment(s) env-Web
Indicator ID: 1 - Environment(s) env-Web
Type: Positive
HTTP response headers contain fingerprinting sensitive fields indicating server's vendors and versions.
Indicator ID: 2 - Environment(s) env-Web
Type: Inconclusive
HTTP response headers do not contain fingerprinting sensitive fields indicating server's vendors and versions.
Security Control ID: 1
Type: Detective
Web application firewall may detect a large amount of HTTP requests from the same host.
Outcome ID: 1
Type: Success
A list of fingerprinting sensitive information from HTTP response headers.
Outcome ID: 1
Type: Failure
There is no HTTP response header information available.
Step 1 - Increase the accuracy of server fingerprinting of Web servers
Attacker usually needs to send several different commands to accurately identify the web server. Attacker can also use automated tools to send requests to the server. The responses of the server may be different in terms of protocol behavior..
Tecnique ID: 1 - Environment(s) env-Web
Tecnique ID: 2 - Environment(s) env-Web
Tecnique ID: 3 - Environment(s) env-Web
Indicator ID: 1 - Environment(s) env-Web
Type: Positive
Find different inner reordering of headers in HTTP response due to different versions of the server.
Indicator ID: 2 - Environment(s) env-Web
Type: Positive
Every server answers to a Bad request in a different way due to different versions of the server.
Indicator ID: 3 - Environment(s) env-Web
Type: Positive
Find signatures of web servers in database of automated tools.
Indicator ID: 4 - Environment(s) env-Web
Type: Negative
HTTP response headers all look like identical.
Security Control ID: 1
Type: Detective
Alert on standard fingerprinting probes. Use the same vulnerability catalogs that adversaries use.
Security Control ID: 2
Type: Detective
Alert on bad request.
Security Control ID: 3
Type: Preventative
Obfuscate server fields of HTTP response.
Security Control ID: 4
Type: Preventative
Hide inner ordering of HTTP response header.
Security Control ID: 5
Type: Preventative
Customizing HTTP error codes such as 404 or 500.
Outcome ID: 1
Type: Success
The attacker successfully identifies server's vendors and versions.
Step 2 - Identify Web Application Software
After the web server platform software has been identified, the attacker start to identify web application technologies such as ASP, .NET, PHP and Java on the server..
Tecnique ID: 1 - Environment(s) env-Web
Tecnique ID: 2 - Environment(s) env-Web
Tecnique ID: 3 - Environment(s) env-Web
Tecnique ID: 4 - Environment(s) env-Web
Indicator ID: 1 - Environment(s) env-Web
Type: Positive
File name extensions can be found in the URL.
Indicator ID: 2 - Environment(s) env-Web
Type: Positive
HTTP Response headers show software version.
Indicator ID: 3 - Environment(s) env-Web
Type: Positive
Cookies leak information for server's version.
Indicator ID: 4 - Environment(s) env-Web
Type: Positive
From error messages, the stack trace of errors and exceptions may also explicitly tell application software information.
Security Control ID: 1
Type: Detective
Alert on standard fingerprinting probes. Use the same vulnerability catalogs that adversaries use.
Security Control ID: 2
Type: Detective
Alert on bad request.
Security Control ID: 3
Type: Preventative
Hide URL file extension.
Security Control ID: 4
Type: Preventative
Hide HTTP response header software information filed.
Security Control ID: 5
Type: Preventative
Hide cookie's software information filed
Security Control ID: 6
Type: Preventative
Appropriately deal with error messages.
Outcome ID: 1
Type: Success
File name extensions can be found in the URL.
Outcome ID: 1
Type: Success
HTTP Response headers show software version.
Outcome ID: 1
Type: Success
Cookies leak information for server's version.
Outcome ID: 1
Type: Success
From error messages, the stack trace of errors and exceptions may also explicitly tell application software information.
Outcome ID: 1
Type: Success
The attacker successfully identifies web application software vendors and versions.
Step 3 - Identify Backend Database Version
Determining the database engine type can assist attackers' attempt to successfully execute SQL injection. Some database API such as ODBC will show a database type as part of the driver information when reporting an error..
Tecnique ID: 1 - Environment(s) env-Web
Indicator ID: 1 - Environment(s) env-Web
Type: Positive
Get error messages from SQL response.
Indicator ID: 2 - Environment(s) env-Web
Type: Negative
No error messages.
Security Control ID: 1
Type: Detective
Alert on standard fingerprinting probes. Use the same vulnerability catalogs that adversaries use.
Security Control ID: 2
Type: Detective
Alert on bad request.
Security Control ID: 3
Type: Preventative
Obfuscate database type in Database API's error message.
Outcome ID: 1
Type: Success
The attacker successfully identifies database type from error messages.
Outcome ID: 2
Type: Failure
The attacker fails to identify database type from error messages.
Implementation: Obfuscate server fields of HTTP response.
Implementation: Hide inner ordering of HTTP response header.
Implementation: Customizing HTTP error codes such as 404 or 500.
Implementation: Hide URL file extension.
Implementation: Hide HTTP response header software information filed.
Implementation: Hide cookie's software information filed.
Implementation: Appropriately deal with error messages.
Implementation: Obfuscate database type in Database API's error message.