An adversary, aware of an application's location (and possibly authorized to use the application), probes an application's structure and evaluates its robustness by submitting requests and examining responses. Often, this is accomplished by sending variants of expected queries in the hope that these modified queries might return information beyond what the expected set of queries would provide.
Description
Attack Execution Flow
4
1
Step 1
Explore[Determine parameters] Determine all user-controllable parameters of the application either by probing or by finding documentation
AI Translation
[Determina i parametri] Identifica tutti i parametri controllabili dall'utente dell'applicazione, sia tramite probing che tramite ricerca di documentazione
2
Step 2
Experiment[Cause error condition] Inject each parameter with content that causes an error condition to manifest
AI Translation
[Indurre condizione di errore] Iniettare in ogni parametro contenuto che provochi la manifestazione di una condizione di errore
3
Step 3
Experiment[Modify parameters] Modify the content of each parameter according to observed error conditions
AI Translation
[Modifica parametri] Modifica il contenuto di ciascun parametro in base alle condizioni di errore osservate
4
Step 4
Exploit[Follow up attack] Once the above steps have been repeated with enough parameters, the application will be sufficiently mapped out. The adversary can then launch a desired attack (for example, Blind SQL Injection)
AI Translation
[Attacco di follow-up] Una volta ripetuti i passaggi sopra con un numero sufficiente di parametri, l'applicazione sarà sufficientemente mappata. L'avversario può quindi lanciare un attacco desiderato (ad esempio, Blind SQL Injection)
Mitigations
2
Application Designers Can Construct A 'Code Book' For Error Messages. When Using A Code Book, Application Error Messages Aren'T Generated In String Or Stack Trace Form, But Are Cataloged And Replaced With A Unique (Often Integer-Based) Value 'Coding' For The Error. Such A Technique Will Require Helpdesk And Hosting Personnel To Use A 'Code Book' Or Similar Mapping To Decode Application Errors/Logs In Order To Respond To Them Normally.
Application Designers Can Wrap Application Functionality (Preferably Through The Underlying Framework) In An Output Encoding Scheme That Obscures Or Cleanses Error Messages To Prevent Such Attacks. Such A Technique Is Often Used In Conjunction With The Above 'Code Book' Suggestion.
Consequences
Security Scopes Affected
Confidentiality
Potential Impacts
Read Data
Indicators
1
Repeated errors generated by the same piece of code are an indication, although it requires careful monitoring of the application and its associated error logs, if any.
Relationships
Resources Required
1
The Attacker needs the ability to probe application functionality and provide it erroneous directives or data without triggering intrusion detection schemes or making enough of an impact on application logging that steps are taken against the adversary.
The Attack does not need special hardware, software, skills, or access.