CVE-2026-27910
Published: 14 April 2026
Summary
CVE-2026-27910 is a high-severity Improper Handling of Insufficient Permissions or Privileges (CWE-280) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 16.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and AC-6 (Least Privilege).
Deeper analysis
CVE-2026-27910 is a vulnerability in Windows Installer stemming from improper handling of insufficient permissions or privileges, classified under CWE-280. This flaw affects Windows systems utilizing the Windows Installer component and was published on 2026-04-14. The CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) reflects its high severity due to local privilege escalation potential.
A local attacker with low privileges (PR:L) can exploit this vulnerability with low attack complexity and no user interaction. Exploitation requires only local access (AV:L) and results in high impacts on confidentiality, integrity, and availability, allowing the attacker to elevate to system-level privileges and potentially fully compromise the affected host.
Microsoft's update guide provides details on mitigation, available at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-27910. Security practitioners should consult this advisory for patching instructions and any recommended workarounds.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-22449
Vulnerability details
Improper handling of insufficient permissions or privileges in Windows Installer allows an authorized attacker to elevate privileges locally.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Local privilege escalation vulnerability in Windows Installer (CWE-280) directly enables T1068 Exploitation for Privilege Escalation from low-privileged local access to SYSTEM.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly mitigates CVE-2026-27910 by requiring timely remediation of the Windows Installer vulnerability through vendor patches.
Enforces least privilege for local users and processes, limiting the scope and impact of privilege escalation exploits in Windows Installer.
Requires the system to enforce approved access control policies, directly addressing the improper handling of permissions or privileges in Windows Installer.