Cyber Resilience

CVE-2026-27910

Microsoft Windows 10 21H2 ≤ 10.0.19044.7184

Published
14 April 2026
Modified
23 April 2026
Patch / advisory
CVSS Score v3.1 7.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0021 11th percentile
Risk Priority 55 floored blend · peak EPSS

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, ranked at the 11th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-24 (Access Control Decisions) and AC-25 (Reference Monitor) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

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.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Improper handling of insufficient permissions or privileges in Windows Installer allows an authorized attacker to elevate privileges locally.

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-50170Same product: Microsoft Windows 10 1809
CVE-2026-20817Same product: Microsoft Windows 10 21H2
CVE-2024-43636Same product: Microsoft Windows 10 1607
CVE-2024-49079Same product: Microsoft Windows 10 1607
CVE-2024-43646Same product: Microsoft Windows 10 1607
CVE-2024-49138Same product: Microsoft Windows 10 1607
CVE-2024-49122Same product: Microsoft Windows 10 1607
CVE-2024-49088Same product: Microsoft Windows 10 1607
CVE-2024-43627Same product: Microsoft Windows 10 1607
CVE-2024-49072Same product: Microsoft Windows 10 1607

Affected Assets

microsoft
windows 10 1607
≤ 10.0.14393.9060 · ≤ 10.0.14393.9060
microsoft
windows 10 1809
≤ 10.0.17763.8644 · ≤ 10.0.17763.8644
microsoft
windows 10 21h2
≤ 10.0.19044.7184 · ≤ 10.0.19044.7184 · ≤ 10.0.19044.7184
microsoft
windows 10 22h2
≤ 10.0.19045.7184 · ≤ 10.0.19045.7184 · ≤ 10.0.19045.7184
microsoft
windows 11 23h2
≤ 10.0.22631.6936 · ≤ 10.0.22631.6936
microsoft
windows 11 24h2
≤ 10.0.26100.8246 · ≤ 10.0.26100.8246
microsoft
windows 11 25h2
≤ 10.0.26200.8246 · ≤ 10.0.26200.8246
microsoft
windows 11 26h1
≤ 10.0.28000.1836 · ≤ 10.0.28000.1836
microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
≤ 10.0.14393.9060
+4 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.2.2
  • V8.3.3

Mitigating Controls (NIST 800-53 r5) AI

Ensuring access decisions are applied to every request structurally prevents the product from taking unexpected paths when privileges are lacking.

A reference monitor that is always invoked guarantees privilege checks occur, eliminating the root condition for improper insufficient-privilege handling.

Access enforcement directly stops code from proceeding on insufficient privileges by applying authorization checks before resource access.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

Defining, enforcing and reviewing access permissions with least privilege directly prevents code paths that mishandle insufficient privileges.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data surfaces adverse events triggered by unhandled permission failures.

PR.PS-04 partial match
prevents

Generating logs of permission-related events enables detection and analysis of improper handling.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect missing or incorrect privilege handling.

prevents

Defines access-control policy that should prevent insufficient-privilege situations.

degrades

Specifies how access rights are granted, reviewed and revoked, directly addressing privilege handling.

degrades

Requires explicit management of privileged access rights, reducing the chance of missing privilege checks.

prevents

Secure-SDLC practices include privilege checks during design and coding.

prevents

Secure-coding standards require proper permission checks before resource access.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (2 rules)
  • V-248548 OL 8 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-280
  • V-248596 OL 8 must enable the SELinux targeted policy. prevents CWE-280
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-280
RHEL 9 (2 rules)
  • V-258078 RHEL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-280
  • V-272496 RHEL 9 must elevate the SELinux context when an administrator calls the sudo command. prevents CWE-280

References