timing_attack
Profile web applications, sorting inputs into two categories based on discrepancies in the application's response time.
If you need a known-vulnerable application for testing and/or development, see Camelflage.
Installation
% gem install timing_attackUsage
timing_attack [options] -u <target> <inputs>
-u, --url URL URL of endpoint to profile. 'INPUT' will be replaced with the attack string
-n, --number NUM Requests per input (default: 50)
-c, --concurrency NUM Number of concurrent requests (default: 15)
-t, --threshold NUM Minimum threshold, in seconds, for meaningfulness (default: 0.025)
-p, --post Use POST, not GET
-q, --quiet Quiet mode (don't display progress bars)
-b, --brute-force Brute force mode
-i, --inputs-file FILE Read inputs from specified file, one per line
--parameters STR JSON hash of URL parameters. 'INPUT' will be replaced with the attack string
--parameters-file FILE Name of file containing parameters as with --parameters
--headers STR JSON hash of headers. 'INPUT' will be replaced with the attack string
--headers-file FILE Name of file containing headers as with --headers
--body STR JSON hash of parameters to be included in the request body. 'INPUT' will be replaced with the attack string
--body-file FILE Name of file containing parameters as with --body
--http-username STR HTTP basic authentication username. 'INPUT' will be replaced with the attack string
--http-password STR HTTP basic authentication password. 'INPUT' will be replaced with the attack string
--percentile NUM Use NUMth percentile for calculations (default: 3)
--mean Use mean for calculations
--median Use median for calculations
-v, --version Print version information
-h, --help Display this screen
Note that setting concurrency too high can add significant jitter to your results. If you know that your inputs contain elements in both long and short response groups but your results are bogus, try backing off on concurrency. The default value of 15 is a good starting place for robust remote targets, but you might need to dial it back to as far as 1 (especially if you're attacking a single-threaded server)
For the url, body, headers, --http-password, http-username, and
parameters options, the string INPUT can be included. It will be replaced
with the current test string.
The body, headers, and parameters options take objects serialized with
JSON.
Enumeration
Consider that we we want to gather information from a Rails server running
locally at http://localhost:3000. Let's say that we know the following:
[email protected]exists in the database[email protected]does not exist in the database
and we want to know if [email protected] and [email protected] exist in
the database.
We execute (using -q to suppress the progress bar)
% timing_attack -q -u 'http://localhost:3000/timing/conditional_hashing?login=INPUT&password=123' \
[email protected] [email protected] \
[email protected] [email protected]Short tests:
[email protected] 0.0031
[email protected] 0.0033
Long tests:
[email protected] 0.1037
[email protected] 0.1040
Note that you don't need to know anything about the database when attacking. It is, however, nice to have a bit of information as a sanity check.
Brute Forcing
Consider that we know the endpoint
http://localhost:3000/timing/string_comparison is vulnerable to a timing
attack due to an early return in string comparison. We can attack it with
timing_attack -u http://localhost:3000/timing/string_comparison \
--parameters '{"password":"INPUT"}' \
--brute-forceThis will attempt a brute-force timing attack against against the password
parameter.
Specifying inputs
The URL itself (--url), URL parameters (--parameters), HTTP body
(--body), and HTTP headers (--headers) can all contain the string INPUT.
INPUT will be replaced with the current attack string, whether it is
specified on the command line (as in enumeration mode), or generated by
timing_attack (as in brute force mode).
To perform a timing attack against HTTP basic authentication, --http-username
and --http-password can be specified. INPUT will be replaced with the
current attack string as above.
The --parameters and --body options must be specified in JSON format.
Reading from files
Body contents, parameters, headers, and inputs can all be read from a file
specified on the comamnd line with --body-file, --parameters-file,
--headers-file, and --inputs-file respectively. --body-file,
--parameters-file, and --headers-file expect the file's contents to be a
JSON hash; --inputs-file simply expects one input per line.
Example:
% cat inputs.txt
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
% cat params.txt
{"login":"INPUT", "password":"123", "delta":"10"}
% timing_attack -q -u "http://localhost:3000/timing/login" \
--parameters-file params.txt \
--inputs-file inputs.txt
Short tests:
[email protected] 0.0023
[email protected] 0.0025
Long tests:
[email protected] 0.1042
[email protected] 0.1046
[email protected] 0.1051
[email protected] 0.1054
How it works
The various inputs are each thrown at the endpoint --number times. The
--percentileth percentile of each input's results is considered the
representative result for that input. Inputs are then sorted according to
their representative results and the largest spike in their graph is found.
Results are then split into short and long groups according to this spike.
The --mean flag uses the average of results for a particular input as its
representative result. The --median flag simply uses the 50th percentile.
According to Crosby, Wallach, and
Reidi, results
with percentiles above ~15, median, and mean are all quite noisy, so you should
probably keep --percentile low.
I was very surprised to find that I get correct results against remote targets
with --number around 20. Default is 50, as that has been sufficient in my tests
for LAN and local targets.
Contributing
Bug reports and pull requests are welcome here.
Disclaimer
timing_attack is quick and dirty.
Also, don't use timing_attack against machines that aren't yours.