WinAFL TinyInst build fails at runtime – libipt.dll was not found error when running afl-fuzz.exe

[ronnieecolab]

I built WinAFL using TinyInst instrumentation mode. The build process completed successfully, but when I try to run afl-fuzz.exe, I get a runtime error indicating that libipt.dll is missing.

My understanding is that TinyInst mode should not require Intel PT (libipt.dll), so I am unsure why this dependency is being requested.

Environment
OS: Windows 10 x64
WinAFL build type: TinyInst instrumentation
Compiler: Visual Studio (ReleaseWithDebInfo build)
WinAFL source: latest GitHub version
Target binary: imageharness.exe

Command Used
afl-fuzz.exe -y -i C:\img_fuzz_input -o C:\img_fuzz_output -t 5000 --
-instrument_module imageharness.exe
-target_module imageharness.exe
-target_method fuzz
-nargs 1
-iterations 5000
-persist
-loop --
"C:\Users\wtf\source\repos\imageharness\x64\Release\imageharness.exe" "@@"

Error Message
afl-fuzz.exe - System Error
The code execution cannot proceed because libipt.dll was not found.
Reinstalling the program may fix this problem.

[ifratric]

You're right, TinyInst mode shouldn't require libipt. Can you post the exact commands you used to build WinAFL? Does adding/removing -DINTELPT=1 in the cmake command line fix the problem?

[ronnieecolab]

C:\Users\wtf\Desktop\winafl\build_tinyinst>mkdir build_tinyinst
C:\Users\wtf\Desktop\winafl\build_tinyinst>cd build_tinyinst
C:\Users\wtf\Desktop\winafl\build_tinyinst>cmake -A x64 -DTINYINST=1 -DCMAKE_POLICY_VERSION_MINIMUM=3.5 ..
C:\Users\wtf\Desktop\winafl\build_tinyinst>cmake --build . --config RelWithDebInfo

[ifratric]

I tried but I couldn't reproduce the issue. I also couldn't see any place in the build files where libipt is referenced unless -DINTELPT is set. Perhaps your build directory is polluted by some previous build that also included libipt?

[ronnieecolab]

Thanks for the suggestion. I cleaned the build directory and performed a fresh build of WinAFL using TinyInst without enabling -DINTELPT. However, I am still encountering the same libipt.dll missing error when running afl-fuzz.exe.