KB4551762 Security Update for SMBv3 Flaw Released by Microsoft

Technology giant Microsoft issued the KB4551762 security update to fix the pre-auth RCE Windows 10 flaw discovered in Microsoft Server Message Block 3.1.1 (SMBv3).

Tracked as CVE-2020-0796, the KB4551762 security update addresses “a network communication protocol issue that provides shared access to files, printers, and serial ports,” according to Microsoft.

KB4551762 can be installed by checking for updates via Windows Update or by physically downloading it for your Windows version from the Microsoft Update Catalog.

“While we have not observed an attack exploiting this vulnerability, we recommend that you apply this update to your affected devices with priority,” Microsoft says.

Termed SMBGhost or EternalDarkness, the flaw only affects devices running Windows 10, version 1903 and 1909, and Windows Server Server Core installations, versions 1903 and 1909.

The company explicated that the susceptibility only exists in a new feature added to Windows 10 version 1903 and that older versions of Windows do not offer support for SMBv3.1.1 compression, the feature behind this bug.