CVE-2026-40420
Published: 12 May 2026
Summary
CVE-2026-40420 is a high-severity Improper Access Control (CWE-284) vulnerability. Its CVSS base score is 8.8 (High).
Operationally, it is not currently listed in the CISA KEV catalog.
Threat & Defense Details
Likely Mitigating ControlsAI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
The access control policy and procedures directly mandate and enforce proper access control mechanisms across the organization.
Device lock enforces restricted access until re-authentication, directly reducing unauthorized use of active sessions.
Supervision and review of access control activities directly detects and remediates improper access configurations or usages.
Explicitly identifying and documenting actions permitted without identification or authentication enforces proper access control boundaries by defining justified exceptions.
By automatically labeling outputs with security attributes, the control supports attribute-based enforcement and reduces exploitability of improper access control weaknesses.
Associating and retaining security attributes with data directly supports enforcement of access control decisions across storage, processing, and transmission.
Requiring prior authorization for each remote access type prevents improper access control over remote connections.
Requiring authorization of wireless access before allowing connections enforces proper access control for this access method.
NVD Description
Improper access control in Microsoft Office Click-To-Run allows an authorized attacker to elevate privileges locally.
Deeper analysisAI
Automated synthesis unavailable for this CVE.
Details
- CWE(s)