Microsoft Windows users beware of Vulnerability-related.DiscoverVulnerability an unpatched memory corruption bug which could be exploited Vulnerability-related.DiscoverVulnerability to cause denial of service ( DoS ) attacks as well as other exploits . The vulnerability is in the SMB ( Server Message Block ) and is caused by the platform 's inability to properly handle a specially-crafted server response that contains too many bytes following the structure defined in the SMB2 TREE_CONNECT Response structure , according to a Feb 2 CERT advisory . If a user connects to a malicious SMB server , a vulnerable Windows client system may crash and display a blue screen of death ( BSOD ) in mrxsmb20.sys , the advisory said . Researchers have confirmed Vulnerability-related.DiscoverVulnerability the flaw affects Vulnerability-related.DiscoverVulnerability fully-patched Windows 10 and Windows 8.1 client systems , as well as the server equivalents of these platforms , Windows Server 2016 and Windows Server 2012 R2 . The vulnerability is still being examined and it is possible that the flaw may enable more exploits as well . A researcher by the moniker “ PythonResponder ” first reported Vulnerability-related.DiscoverVulnerability the zero day and a proof-of-concept code was published to GitHub shortly after . It is recommended that users consider blocking outbound SMB connections from the local network to the WAN in order to prevent remote attackers from causing denial of service attacks