User-Friendly Fuzzing with Sienna Locomotive

Summary: Trail of Bits released Sienna Locomotive, an open-source fuzzer for Windows built for usability rather than speed or coverage gains. It configures a target with just an executable path and command line string, scans a running program for input-taking functions like ReadFile or fread to target, and triages crashes by severity using a reimplementation of Breakpad and !exploitable heuristics augmented with Winchecksec and a custom taint tracer.
What you should know: The article notes Windows holds 75+% market share while most fuzzers are built for Unix, and that OpenSSL ran on at least two-thirds of web servers in 2014 yet Heartbleed took over two years to find - the gap Sienna Locomotive is aimed at is developers who never set up a fuzzer at all.

Read the original at Trail of Bits Blog ↗

Topics: Supply Chain & AppSec
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