https://github.com/salmonx/dictionaries

Fuzzing dictionaries for afl-fuzz/LibFuzzer
https://github.com/salmonx/dictionaries

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Fuzzing dictionaries for afl-fuzz/LibFuzzer

• Host: GitHub
• URL: https://github.com/salmonx/dictionaries
• Owner: salmonx
• Created: 2021-06-04T07:33:13.000Z (over 3 years ago)
• Default Branch: main
• Last Pushed: 2021-07-23T03:30:13.000Z (over 3 years ago)
• Last Synced: 2024-08-05T17:41:42.945Z (4 months ago)
• Homepage:
• Size: 150 KB
• Stars: 86
• Watchers: 2
• Forks: 5
• Open Issues: 0
• Metadata Files:
  • Readme: README.dictionaries

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• awesome-hacking-lists - salmonx/dictionaries - Fuzzing dictionaries for afl-fuzz/LibFuzzer (Others)

README

        
================

AFL dictionaries

================

  (See ../docs/README for the general instruction manual.)

This subdirectory contains a set of dictionaries that can be used in

conjunction with the -x option to allow the fuzzer to effortlessly explore the

grammar of some of the more verbose data formats or languages. The basic

principle behind the operation of fuzzer dictionaries is outlined in section 9

of the "main" README for the project.

Custom dictionaries can be added at will. They should consist of a

reasonably-sized set of rudimentary syntax units that the fuzzer will then try

to clobber together in various ways. Snippets between 2 and 16 bytes are usually

the sweet spot.

Custom dictionaries can be created in two ways:

  - By creating a new directory and placing each token in a separate file, in

    which case, there is no need to escape or otherwise format the data.

  - By creating a flat text file where tokens are listed one per line in the

    format of name="value". The alphanumeric name is ignored and can be omitted,

    although it is a convenient way to document the meaning of a particular

    token. The value must appear in quotes, with hex escaping (\xNN) applied to

    all non-printable, high-bit, or otherwise problematic characters (\\ and \"

    shorthands are recognized, too).

The fuzzer auto-selects the appropriate mode depending on whether the -x

parameter is a file or a directory.

In the file mode, every name field can be optionally followed by @, e.g.:

  keyword_foo@1 = "foo"

Such entries will be loaded only if the requested dictionary level is equal or

higher than this number. The default level is zero; a higher value can be set

by appending @ to the dictionary file name, like so:

  -x path/to/dictionary.dct@2

Good examples of dictionaries can be found in xml.dict and png.dict.