https://www.theregister.co.uk/2018/04/04/microsoft_windows_defender_rar_bug/
A remote-code execution vulnerability in Windows Defender – a flaw that can be exploited by malicious .rar files to run malware on PCs – has been traced back to an open-source archiving tool Microsoft adopted for its own use.
[...] Apparently, Microsoft forked that version of unrar and incorporated the component into its operating system's antivirus engine. That forked code was then modified so that all signed integer variables were converted to unsigned variables, causing knock-on problems with mathematical comparisons. This in turn left the software vulnerable to memory corruption errors, which can crash the antivirus package or allow malicious code to potentially execute.
(Score: 2) by DannyB on Monday April 09 2018, @09:13PM
Shhhhhh! If unrar isn't open source, how will Microsoft be able to bad mouth open source?
The lower I set my standards the more accomplishments I have.