SB20260114104 - Multiple vulnerabilities in Microsoft Office

Description

This security bulletin contains information about 3 vulnerabilities.

1) Untrusted search path (CVE-ID: CVE-2026-20943)

CWE-ID: CWE-426 - Untrusted Search Path

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

The vulnerability allows a remote attacker to execute arbitrary code on the system.

The vulnerability exists due to usage of an untrusted search path in Microsoft Office Click-To-Run. A remote attacker can trick a victim to open a specially crafted file and execute arbitrary code with escalated privileges.

2) Use-after-free (CVE-ID: CVE-2026-20952)

CWE-ID: CWE-416 - Use After Free

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

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in Microsoft Office. A remote attacker can run a specially crafted application and execute arbitrary code on the target system.

3) Use-after-free (CVE-ID: CVE-2026-20953)

CWE-ID: CWE-416 - Use After Free

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

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in Microsoft Office. A remote attacker can run a specially crafted application and execute arbitrary code on the target system.

Remediation

Install update from vendor's website.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20943
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20952
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20953