SB2019111310 - Multiple vulnerabilities in Microsoft Windows NetLogon

Description

This security bulletin contains information about 2 vulnerabilities.

1) Improper Authentication (CVE-ID: CVE-2019-1384)

CWE-ID: CWE-287 - Improper Authentication

CVSSv4: CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to the NETLOGON message is able to obtain the session key and sign messages. A remote authenticated attacker can send a specially crafted authentication request, bypass authentication process and gain unauthorized access to another machine using the original user privileges.

2) Man-in-the-Middle (MitM) attack (CVE-ID: CVE-2019-1424)

CWE-ID: CWE-300 - Channel Accessible by Non-Endpoint ('Man-in-the-Middle')

CVSSv4: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to perform a man-in-the-middle (MitM) attack.

The vulnerability exists due to the Windows Netlogon improperly handles a secure communications channel. A remote attacker can perform a man-in-the-middle attack and downgrade aspects of the connection allowing for further modification of the transmission.

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1384
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1424