Microsoft has said it will not patch a two-decade-old Windows SMB vulnerability, called SMBloris because it behaves comparably to the Slowloris attacks. The flaw will be disclosed and demonstrated during DEF CON.

Microsoft released an emergency update for a zero-day vulnerability disclosed by Google in the Microsoft Malware Protection Engine bundled with most versions of Windows.

Google Project Zero researchers Tavis Ormandy and Natalie Silvanovich found a remotely exploitable Windows vulnerability that Ormandy called he worst in recent memory.

Microsoft said a Windows SMB zero day, which has a public proof-of-concept exploit available, is low risk and won’t be patched until an upcoming Patch Tuesday.

Attackers can leverage a design weakness in all versions of Windows to carry out code injection attacks that bypass detection by security software.