SB2021071364 - Multiple vulnerabilities in Microsoft Windows LSA

Description

This security bulletin contains information about 2 vulnerabilities.

1) Input validation error (CVE-ID: CVE-2021-33788)

CWE-ID: CWE-20 - Improper input validation

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

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input in the Windows LSA. A remote attacker can pass specially crafted input to the application and perform a denial of service (DoS) attack.

2) Security features bypass (CVE-ID: CVE-2021-33786)

CWE-ID: CWE-254 - Security Features

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/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 security feature bypass issue in Windows LSA. A remote authenticated attacker can gain elevated privileges on the target system.

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33788
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33786