Certfuzz Versions Save

(These release notes are copied from our 5 October 2016 blog post announcing the release of BFF 2.8)

Announcing the release of the CERT Basic Fuzzing Framework Version 2.8 (BFF 2.8). It's been about three years since we released BFF 2.7. In this post, I highlight some of the changes we've made.

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Release notes for versions prior to 2.8 can be found here

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Your FOE Is Now Your BFF

To help reduce confusion over our fuzzing tools, the CERT Failure Observation Engine (FOE) is now known as BFF for Windows. For the past few versions, we have been converging the code bases for BFF and FOE into a unified architecture. While a few platform-specific differences remain, the name change reflects the fact that they are now essentially the same product with multi-platform support.

For clarity in this post, I'll refer to BFF for if we're talking about something platform-specific; otherwise I'll refer to BFF for features that are supported across platforms.

Significant Changes

BFF 2.8 has undergone a lot of changes since 2.7 was last released. Here is an overview of some of the bigger changes.

Configurable Mutators (New to Linux and OSX)

BFF for Linux and OSX now use the same configurable mutators as BFF for Windows. Prior to this release, BFF supported only bitwise mutation because it relied on zzuf for fuzzing and crash detection. FOE, on the other hand, had configurable mutators from day one, but was only available for Windows. With BFF 2.8, all platforms now default to using the bytemut mutator, which we have found to be more effective at searching the input space for crashing test cases.

BFF still uses zzuf on Linux and OSX for crash detection, but all mutation is now done directly in BFF's python code.

Verify Mode (New to Linux and OSX)

Having configurable mutators permits us to have a null mutator that does not modify the input files at all. As a result, Linux and OSX now support verify mode, another feature previously available only on FOE on Windows.

Verify mode can be useful in a few situations, including the following:

1. Say you've previously run BFF against a piece of software and found crashing test cases. At some point, if a newer version of the software becomes available, you might want to check to see which of the test cases are now fixed.
2. If you've got crashing test cases from another fuzzer, like American Fuzzy Lop (afl) or Peach Fuzzer, you could triage them using verify mode to run each test case through BFF's test case analysis pipeline to collect debugger output, exploitability estimates, core dumps, valgrind output, etc.

To use BFF in verify mode, do the following:

• Take the old crashing test cases and use them as seed files. This approach can be accomplished using tools/copycrashers.py.
• Run them through BFF in verify mode. Remember to configure the campaign to use the new version of the program you want to check them against.
• Look at the results directory to see which test cases are still a problem.

Drillresults on Every New Crash (All Platforms)

Drillresults was originally included with FOE 2.0 for Windows as a standalone script that you could run to identify easily exploitable vulnerabilities from a fuzzing campaign's results after the fact. Later we added it to BFF for Linux and OSX, but it remained as a standalone script.

In BFF 2.8, drillresults is now run automatically on each crash as part of BFF's post-crash analysis pipeline. Each crashing testcase directory now contains a file with the .drillresults extension containing that information.

Architecture (All Platforms)

Under the hood, we've done quite a bit of refactoring to eliminate redundancies across the Linux and Windows codebases. The overall BFF architecture is now platform agnostic, with OS-specific code implemented in separate modules and subclasses where necessary. This consolidation allows us to more easily add new features across all the platforms that BFF supports without having to duplicate any more code than necessary.

Support for Recent OSX Versions

BFF for OSX should work on Mavericks, Yosemite, El Capitan, and Sierra.

Added !analyze Output (Windows)

BFF for Windows collects !analyze -v output (via CDB) for each unique crashing test case. Microsoft published more information about !analyze in their debugger reference materials.

Updated !exploitable (Windows)

BFF for Windows now uses Microsoft's !exploitable version 1.6.

Simplified Configuration (All Platforms)

The BFF configuration file, bff.yaml, was simplified to make configuring fuzzing campaigns easier.

Self-Update Capability (All Platforms)

BFF includes a utility called updatebff.py in the tools directory. Simply run tools/updatebff.py (or on Windows, tools\updatebff.py) to install the latest certfuzz code from GitHub.

Contributing and GitHub Availability

In early 2014 we converted our development process from svn to git, which also allows us to start pushing the work-in-progress code to GitHub. While our day-to-day development still happens in house, having the code available on GitHub allows us to work more directly with, and be more responsive to, outside contributors. It also gives BFF users a place to report bugs or make feature requests.

You can find the code on GitHub. You can also report a bug or request a feature on GitHub.

Download BFF

BFF 2.8 is available for download on our website.

Change Log for BFF 2.8

Bug

• [BFF-178] - Updated config file should trump cached config
• [BFF-262] - FOE null runner heisenbug / unable to get md5 issues
• [BFF-294] - BFF on Windows should cancel any remaining timers on finishing campaign
• [BFF-311] - Standalone Windows minimizer is creating zero-length msec files
• [BFF-312] - Minimizer giving up before it should
• [BFF-464] - Issues with OSX installer results directories
• [BFF-485] - tools/repro.py doesn't support OS X
• [BFF-512] - BFF should handle KeyboardInterrupts more gracefully
• [BFF-515] - Permission denied when doing a zip-based minimization to string
• [BFF-521] - Probability out of range in certfuzz.scoring.multiarmed_bandit.arms.base
• [BFF-533] - Pin_calltrace doesn't play nice with minimizer
• [BFF-534] - certfuzz.test.fuzztools.test_rangefinder.Test.test_get_ranges fails sometimes
• [BFF-742] - reboot recovery currently broken in develop branch
• [BFF-743] - git-based make_dist.py zip missing "results" directory
• [BFF-745] - BFF creating bff.log in ~/pintool on Linux
• [BFF-748] - Remove Android code from main development branch
• [BFF-751] - use subprocess.check_call instead of subprocess.call
• [BFF-754] - BFF OSX installer isn't including crashwrangler source zip
• [BFF-756] - Allow batch.sh to take arguments
• [BFF-764] - Calltracefile is not defined in minimizer_base.py
• [BFF-766] - Don't install Python on Yosemite
• [BFF-778] - BFF should check for zzuf at startup
• [BFF-792] - tmp_reaper isn't cleaning up symlinks
• [BFF-793] - gdb output mostly empty on Ubuntu 15.04
• [BFF-794] - drillresults broken
• [BFF-796] - zzuf won't compile on Ubuntu 15.04
• [BFF-798] - drillresults can truncate addresses with 64-bit apps
• [BFF-799] - quickstats.sh is broken
• [BFF-800] - repro.py doesn't work
• [BFF-801] - _cache_app probably shouldn't set use_shell=True
• [BFF-802] - repro.py can't find config
• [BFF-803] - restarting the watchdog only makes sense for UbuFuzz
• [BFF-804] - zzuf seeing signal 9 on every gnash iteration
• [BFF-818] - Windows hook isn't detecting crashes
• [BFF-819] - BFF should verify filesystem when checking for already-existing crashes.
• [BFF-821] - drillresults is broken on Windows
• [BFF-824] - UbuFuzz should have python hcluster
• [BFF-825] - UbuFuzz needs X to be able to be zapped
• [BFF-826] - BFF removes bad zip files before it can run them
• [BFF-827] - zzuf copy mode file I/O is redundant in the new BFF architecture
• [BFF-828] - Minimizer should be zip-aware
• [BFF-829] - BFF isn't touching the watchdog file
• [BFF-831] - quickstats.py is broken
• [BFF-834] - Raised errors in minimizer kill the campaign
• [BFF-835] - drillresults shouldn't complain when the debugger file it's looking for doesn't have what it needs
• [BFF-836] - minimizer_plot.py doesn't work
• [BFF-837] - drillresults can use way too much memory
• [BFF-839] - Drop fuzzer doesn't work
• [BFF-840] - BFF attempts to minimize non-minimizeable fuzzers
• [BFF-841] - Linux BFF increments stats twice
• [BFF-843] - When valgrind is disabled, callgrind annotation still runs
• [BFF-844] - BFF raises an exception when the first seedfile is exhausted
• [BFF-845] - BFF doesn't have the capability of removing seedfiles from the set
• [BFF-846] - Debug mode hangs with winpdb stuff installed
• [BFF-847] - Stopping BFF campaign doesn't stop killproc.sh
• [BFF-849] - Total stack corruption: 'AnalyzerEmptyOutputError' is not defined
• [BFF-850] - UbuFuzz needs x86 compatibility libs
• [BFF-851] - EFA is incorrect for LInux ReturnAv
• [BFF-856] - BFF Windows minimizes regardless of what bff.yaml says
• [BFF-860] - Crash recycling isn't working
• [BFF-862] - BFF verify mode never finishs
• [BFF-879] - Many tools don't work anymore, looking for config_linux
• [BFF-880] - BFF incorrectly includes the program name in the run line of the gdb template
• [BFF-885] - BFF stops fuzzing - No such file or directory in output_parsers
• [BFF-886] - BFF doesn't use correct gdb cmdline when minimizing
• [BFF-887] - BFF doesn't work on Windows versions newer than XP
• [BFF-888] - BFF doesn't work on Windows - DummyCfg
• [BFF-889] - BFF minimizer tries to delete files from underneath itself
• [BFF-890] - BFF OSX isn't using the latest code
• [BFF-891] - BFF doesn't support El Capitan
• [BFF-892] - Crashwrangler doesn't support El Capitan
• [BFF-894] - BFF stops fuzzing - in-use file
• [BFF-896] - pyyaml installation triggers cmdline tools installation (asynchronously) on El Capitan
• [BFF-897] - BFF unnecessarily tries to install python packages on El Capitan
• [BFF-898] - BFF needs to look for exc_handler_elcapitan
• [BFF-903] - OSX installer isn't including crashwrangler source zip
• [BFF-904] - After fuzzing for a while, the campaign stops seeing the KeyboardInterrupt
• [BFF-905] - BFF isn't getting register values out of CrashWrangler output
• [BFF-907] - BFF hard-codes the directory of CTT based on ~/bff
• [BFF-908] - UbuFuzz 14.04 doesn't allow watchdog to be started
• [BFF-910] - BFF can leave behind the bff_watchdog file when a campaign quits
• [BFF-912] - BFF keyerror on verify run
• [BFF-913] - drillresults doesn't work for verify mode BFF results
• [BFF-914] - Drillresults on windows only scores the first exception
• [BFF-915] - BFF doesn't exit cleanly when seedfiles are exhausted
• [BFF-918] - BFF isn't keeping track of seedfile try counts
• [BFF-921] - BFF minimizer fails on windows - exclude_unmapped_frames
• [BFF-927] - Windows BFF fails due to NotImplementedError
• [BFF-930] - drillresults thinks that the PC isn't in a loaded module, when it actually is
• [BFF-931] - BFF keep_duplicates option doesn't do anything
• [BFF-932] - Heisenbugs are skipped, regardless of config option
• [BFF-933] - BFF cuts off cdb before it gets the details.
• [BFF-935] - Swap mutator skips zip files
• [BFF-938] - drillresults output is in unix format even on Windows
• [BFF-939] - minimizer on Linux should have option to keep other crashers.
• [BFF-940] - _safe_createzip() takes exactly 2 arguments (3 given)
• [BFF-941] - Watchdog file not touched during standalone minimization
• [BFF-943] - drillresults on Linux is missing some interesting cases
• [BFF-946] - No such thing as a heisenbug if the winrun hook isn't used.
• [BFF-949] - BFF leaves OpenOffice processes behind
• [BFF-952] - BFF on linux no longer hides stdout
• [BFF-954] - drillresults analyzer only lists last exception
• [BFF-955] - drillresults on Windows is missing some interesting cases
• [BFF-957] - BFF is broken on Windows - incorrect number of arguments
• [BFF-961] - TWDF disables itself after enabling itself.
• [BFF-965] - drillresults as an analyzer indicates wrong Fuzzed file: path
• [BFF-967] - BFF shouldn't try to use exploitable on platforms that don't support it
• [BFF-973] - Calltrace parsing can fail
• [BFF-975] - minimizer_log.txt missing from output dirs
• [BFF-978] - Minimizing on system with ASLR and no symbols never stops
• [BFF-984] - valgrind core files being left in BFF directory
• [BFF-985] - debugheap option is ignored on Windows
• [BFF-986] - Minimizer fails to parse total stack corruption
• [BFF-987] - watchcpu key error
• [BFF-988] - Minimizer not including bytemap
• [BFF-989] - Reindroduce keep_unique_faddr support in BFF
• [BFF-990] - tools/repro.py on linux "-f" option doesn't work
• [BFF-991] - tools/minimizer plot doesn't factor in exploitability
• [BFF-992] - tools/callsim.py doesn't factor in exploitability
• [BFF-993] - edb doesn't work in UbuFuzz 16.04
• [BFF-994] - git edb Goto Address isn't working
• [BFF-995] - BFF pintool has too many invalid_rtn function names
• [BFF-996] - BFF minimizer keep other crashers is saving something other than the new crashes
• [BFF-998] - gdb doesn't always reset frame to 0 after doing a "bt full"
• [BFF-999] - BFF refuses to string minimize total stack corruption
• [BFF-1000] - recycle_crashers option doesn't work if minimization is disabled
• [BFF-1002] - BFF appears to remove each seedfile in verify mode multiple times
• [BFF-1004] - .calltrace files are missing from output dirs
• [BFF-1005] - BFF crashes on attempting to save a heisenbug
• [BFF-1006] - BFF shouldn't change into the target directory on first iteration or winrun or repro
• [BFF-1007] - Drillresults fails on 64-bit windows
• [BFF-1008] - Dud msec files shouldn't stop drillresults
• [BFF-1009] - drillresults on 64-bit windows needs to check for 32-bit and 64-bit loaded module patterns
• [BFF-1011] - BFF on Windows is putting PROBABLY_NOT_EXPLOITABLE crashers in UNKNOWN directory
• [BFF-1013] - Include minimize-to-string option in BFF campaign
• [BFF-1014] - faulting addresses reported by gdb on SIGABRTs aren't valid
• [BFF-1015] - Allow verify mode to perform minimization to string
• [BFF-1017] - Some applications change the size of the file being opened

New Feature

• [BFF-177] - BFF should support pluggable file mutators
• [BFF-261] - BFF / FOE minimizer should punt on minimizing inconsistent crashes
• [BFF-328] - Valgrind (and subsequently callgrind) should be optional
• [BFF-436] - Debugger output on OSX should embed a "Found using BFF" message
• [BFF-472] - Integrate FOE's campaign/iteration architecture into BFF on linux/osx
• [BFF-473] - drillresults should become an analyzer
• [BFF-475] - BFF should be able to use virtualenv on all platforms
• [BFF-476] - Integrate FOE's runner into BFF
• [BFF-477] - Create a zzuf-based Runner class
• [BFF-478] - Add Analyzers to BFF on Windows
• [BFF-482] - Add verify mode for BFF
• [BFF-484] - Install ncurses-hexedit in UbuFuzz
• [BFF-503] - minimize.py on Linux and OS X is missing the "-k" (keep other crashes) option
• [BFF-505] - Testcases should support multiple persistence options
• [BFF-772] - Update Crashwrangler to version supporting Yosemite
• [BFF-773] - BFF (FOE) doesn't support Python 2.7.6 or later (Popen)
• [BFF-782] - BFF should use YAML config
• [BFF-789] - Use lldb in tools/repro if available.
• [BFF-809] - Include edb 9.20 in Ubufuzz
• [BFF-810] - Include jed in UbuFUzz
• [BFF-811] - include ncurses-hexedit in UbuFuzz
• [BFF-812] - include hexedit in UbuFuzz
• [BFF-813] - Disable ASLR in UbuFuzz
• [BFF-814] - Don't use UUIDs in /etc/fstab
• [BFF-815] - Include cifs-utils in UbuFuzz
• [BFF-816] - UbuFuzz needs the cert-patched zzuf
• [BFF-817] - Set password for "fuzz" user to "test"
• [BFF-838] - Minimizer on Linux doesn't support the feature to keep other crashes
• [BFF-848] - inetc doesn't check ssl certificates
• [BFF-852] - improper results symlink in UbuFuzz
• [BFF-853] - Include bff-dashboard in UbuFuzz
• [BFF-854] - BFF should not use gdbinit
• [BFF-857] - Disable Dr. Konqui before fuzzing
• [BFF-867] - create certfuzz.reporters package for pipeline reporters
• [BFF-1003] - BFF should include pin tool runner

Task

• [BFF-746] - Unify BFF and FOE licenses
• [BFF-808] - Use CERT logo as UbuFuzz background
• [BFF-871] - Update Jenkins for new network environment

Improvement

• [BFF-207] - refactor/simplify bff_config.py
• [BFF-210] - BFF should use FOE's campaign / iteration objects
• [BFF-269] - FOE should rename msec files for exceptions beyond the first
• [BFF-361] - Refactor certfuzz.scoring.scorable_set
• [BFF-453] - Unique Campaign folders in BFF
• [BFF-468] - Replace fluxbox background in ubufuzz with a CERT/SEI/CMU logo background
• [BFF-469] - bff.cfg has ctrl-Ms
• [BFF-483] - Update BFF installer to include Mavericks version of CrashWrangler
• [BFF-487] - _look_for_crash shows up way too frequently in debug log files
• [BFF-498] - Remove clause 3 (advertising) from FOE license
• [BFF-500] - Include edb 0.9.20 in UbuFuzz
• [BFF-502] - DRY up linux and windows drillresults
• [BFF-506] - BFF's make_dist.py is overly SVN-centric
• [BFF-513] - Eliminate need for debuggers.verify_supported_platform()
• [BFF-514] - replace optparse with argparse in certfuzz.bff.common
• [BFF-528] - BFF should get FOE's rpdb2 / heapy debugger
• [BFF-529] - BFF main module parity across Linux/Windows
• [BFF-530] - Rebrand FOE as BFF
• [BFF-744] - Deduplicate license files
• [BFF-755] - get rid of stop seed in bff config
• [BFF-759] - DRY up iteration_windows and iteration_linux
• [BFF-760] - linux drillresults should cache parsed results
• [BFF-771] - use !exploitable 1.6
• [BFF-774] - Gracefully handle unavailable network
• [BFF-785] - BFF debuggers should be instantiable without requiring an actual debugger present
• [BFF-786] - Get rid of configurable debuggers
• [BFF-788] - BFF on windows should pick the appropriate runner automatically
• [BFF-797] - Update welcome.sh script
• [BFF-858] - BFF should use something other than stdout to collect gdb output
• [BFF-863] - Unify config file options on windows and linux
• [BFF-864] - Linux and Windows are inconsistent in their use of self.cfg vs self.cfg.config
• [BFF-866] - Move certfuzz tests to a peer package of certfuzz
• [BFF-875] - Create testcase logger reporter module
• [BFF-884] - Allow or warn for the presence of IO redirects in command line
• [BFF-893] - BFF runner shouldn't need to be configurable on Windows
• [BFF-899] - remove minimize to string from campaign (keep in standalone)
• [BFF-900] - drillresults should support crashwrangler
• [BFF-902] - BFF should retain double file extensions. e.g. .tar.gz
• [BFF-916] - subprocess_helper should cancel any remaining timers on KeyboardInterrupt
• [BFF-922] - Use a fuzzdir on the local disk.
• [BFF-923] - Drillresults analyzer should use the BFF debugger file parsers
• [BFF-925] - DRY up LinuxTestcase and WindowsTestcase classes
• [BFF-934] - BFF should exhaustively iterate through the end of minimization
• [BFF-947] - BFF can die between tmp_reaper and watchdog file being recreated.
• [BFF-948] - String minimization isn't using the bytemap for the freebie
• [BFF-953] - Replace or remove bff_stats.py
• [BFF-956] - Eliminate per-crash logging
• [BFF-959] - drillresults force mode should ignore existing .drillresults files
• [BFF-963] - Update dependencies installed by BFF installer on Windows
• [BFF-966] - Give debugger-invoked iterations extra time to prevent heisenbugs
• [BFF-968] - BFF should save core dumps for crashes
• [BFF-970] - drillresults should support analyzing a string minimization directory
• [BFF-971] - BFF should clean up empty crash hash directories
• [BFF-972] - BFF should use exploitability in output directory again
• [BFF-979] - Remove testcase-specific logging
• [BFF-980] - remove minimizer_plot.py
• [BFF-982] - Remove killproc.sh
• [BFF-997] - drillresults should fall back to getting the current instruciton w/o "=>"

Sub-task

• [BFF-417] - ScorableSet should not rely on its objects to inherit from ScorableThing
• [BFF-418] - ScorableSet should support use as a generator
• [BFF-419] - ScorableSet should support multiple selection algorithms
• [BFF-420] - Eliminate ScorableThing code
• [BFF-421] - ScorableSet should initialize new additions to have the average of the set as the initial probability
• [BFF-479] - bff.py should become an entry point in setup.py
• [BFF-480] - foe2.py should become an entry point in setup.py
• [BFF-494] - Remove or modify xcat reference in nsis_mid.txt
• [BFF-495] - Refactor build/dist/init.py to parameterize svn repo location
• [BFF-507] - fix make_dist for linux
• [BFF-508] - fix make_dist for windows
• [BFF-509] - fix make_dist for osx
• [BFF-531] - Remove mentions of "foe" from files
• [BFF-532] - Remove mentions of "foe" from file names
• [BFF-739] - Create script to generate epydocs for certfuzz
• [BFF-749] - LinuxCampaign should inherit from CampaignMeta
• [BFF-750] - LinuxCampaign should inherit from CampaignBase
• [BFF-752] - replace subprocess.call with subprocess.check_call in build scripts
• [BFF-753] - replace subprocess.call with subprocess.check_call in certfuzz.fuzztools.subprocess_helper
• [BFF-758] - Integrate iteration_base and iteration_base3
• [BFF-762] - Refactor drillresults into OO code
• [BFF-763] - Create certfuzz.drillresults package
• [BFF-775] - create zzuf-based Fuzzer object
• [BFF-872] - Confirm that ByteMut works on linux
• [BFF-873] - Make fuzzer selection on linux configurable
• [BFF-876] - eradicate "fancy" config objects in favor of simple yaml -> dicts
• [BFF-877] - unify config sections