HOW I DISCOVERED A LIBPNG VULNERABILITY 11 YEARS AFTER IT WAS PATCHED

Summary from the TLDR InfoSec newsletter

While practicing secure code review, the author of this article decided to review the libpng C library. They found that libpng calculated memory allocations based on user-controlled values, such as “depth.” The author was able to trigger a crash using a custom PNG file, but then discovered that the bug was fixed 11 years ago when it was first reported.