SB2026051301 - Multiple vulnerabilities in Microsoft Office Click-To-Run
Published: May 13, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 vulnerabilities.
1) Improper access control (CVE-ID: CVE-2026-40420)
CWE-ID: CWE-284 - Improper Access Control
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 gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to improper access restrictions in Microsoft Office Click-To-Run. A local user can bypass implemented security restrictions and gain elevated privileges on the system.
2) Use-after-free (CVE-ID: CVE-2026-40419)
CWE-ID: CWE-416 - Use After Free
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 compromise vulnerable system.
The vulnerability exists due to a use-after-free error in Microsoft Office Click-To-Run. A local user can gain elevated privileges on the system.
3) Use-after-free (CVE-ID: CVE-2026-40418)
CWE-ID: CWE-416 - Use After Free
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 compromise vulnerable system.
The vulnerability exists due to a use-after-free error in Microsoft Office Click-To-Run. A local user can gain elevated privileges on the system.
4) Insufficient Granularity of Access Control (CVE-ID: CVE-2026-35436)
CWE-ID: CWE-1220 - Insufficient Granularity of Access Control
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 target system.
The vulnerability exists due to insufficient granularity of access control in Microsoft Office Click-To-Run. A local user can gain elevated privileges on the system.
Remediation
Install update from vendor's website.