A year of Windows kernel font fuzzing #1: the results
Summary: Google Project Zero's Mateusz Jurczyk reports that a year of at-scale fuzzing of TrueType and OpenType font handling in the Windows kernel produced 16 vulnerabilities, reported to Microsoft in three iterations beginning 21 May 2015 and fixed between July 2015 and April 2016. The bugs included pool and stack buffer overflows, out-of-bound reads, use-after-free and uninitialized memory issues across win32k.sys and atmfd.dll, most usable for local privilege escalation and some for remote code execution.
What's compelling: Nearly all 16 bugs found on Windows 7 were still present in newer Windows versions, and an RCE inside the restricted user-mode font process on Windows 10 remains viable even after the architectural shift away from the kernel.
Read the original at Google Project Zero ↗
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- Vulnerabilities & Patching
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