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Difference between revisions of "SQL injection/Blind/Extraction"

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(Blind extraction)
 
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== Blind extraction ==  
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=== Blind extraction ===
  
'''There are multiple types of blind data extraction attacks:'''
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'''There are two types of blind SQL extraction attacks:'''
* Timing based
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* Partial-blind: [[comparative precomputation|Pre-computation based]] (Tool: [[mysqli-blindutils]] > [[sqli-hap.py]])
* Pre-computation based
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* Full-blind: [[timing based extraction|Timing based]]
  
'''The only three things that all of these methods have in common is:'''
 
* <u>These attacks</u> are all limited in some fashion because of local environment and latency or remote environment and dataset.
 
* <u>You</u> must not be afraid of programming.
 
  
===Timing-based extraction===
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'''The only things that these methods have in common is:'''
{{warning|<i>If not on a '''LAN''' when this technique is utilized, buggy and unpredictable results '''will''' be attained.</i>}}
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* <u>These attacks</u> are all limited in some fashion because of environment and latency or dataset, respectively.
This testing is ideal when''':
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* <u>Successful exploitation</u> requires automation [[programming]].
* It is taking place on a relatively low latency network
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* There is access to a consistent latency and the remote page has a consistent load time (may not vary by more than 0.5 seconds)
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Single byte exfiltration takes less queries to perform the same results, and leaves a smaller log footprint.
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* A timer will need to be used to see how long it takes the remote server to serve the page.
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Examples of timing-based single-byte exfiltration:
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* <i>Exfiltrating the first character of the database name in a single request:</i>
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{{code|text=<source lang="sql">
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  and sleep(ascii(substring(@@database,1,1)))                  -- MySQL
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  and pg_sleep(ascii(substring(current_database,1,1))) is null -- PostgreSQL
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</source>}}
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:'''By timing these (in seconds) the integer value of the ascii code of the first character of the database will be attained.'''
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Latest revision as of 03:01, 21 November 2012

Blind extraction

There are two types of blind SQL extraction attacks:


The only things that these methods have in common is:

  • These attacks are all limited in some fashion because of environment and latency or dataset, respectively.
  • Successful exploitation requires automation programming.