SB2020031028 - Multiple vulnerabilities in Microsoft Windows Hard Link

Description

This security bulletin contains information about 4 vulnerabilities.

1) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-0849)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the way Windows handles hard links. A local user can create a malicious application, launch it on the system and overwrite a targeted file leading to an elevated status.

To exploit this vulnerability, an attacker would first have to log on to the system.

2) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-0841)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the way Windows handles hard links. A local user can create a malicious application, launch it on the system and overwrite a targeted file leading to an elevated status.

To exploit this vulnerability, an attacker would first have to log on to the system.

3) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-0840)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the way Windows handles hard links. A local user can create a malicious application, launch it on the system and overwrite a targeted file leading to an elevated status.

To exploit this vulnerability, an attacker would first have to log on to the system.

4) Permissions, Privileges, and Access Controls (CVE-ID: CVE-2020-0896)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to the way Windows handles hard links. A local user can create a malicious application, launch it on the system and overwrite a targeted file leading to an elevated status.

To exploit this vulnerability, an attacker would first have to log on to the system.

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0849
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0841
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0840
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0896