SciLexer.dll in Scintilla in Notepad++ (x64) before 7.7 allows remote code execution or denial of service via Unicode characters in a crafted .ml file.
https://www.scintilla.org/ScintillaHistory.html
https://notepad-plus-plus.org/download/v7.7.html
https://github.com/bi7s/CVE/tree/master/CVE-2019-16294
http://packetstormsecurity.com/files/154706/Notepad-Code-Execution-Denial-Of-Service.html