CVE-2026-56176: Windows Win32k Elevation of Privilege Vulnerability

highCVSS 7.8CVE-2026-56176

Out-of-bounds read in Windows Win32K - GRFX allows an authorized attacker to elevate privileges locally.

CSIRTS triage

vendor: Microsoft product: Windows Win32k Privilege escalation

What: An out-of-bounds read vulnerability allows an authorized attacker to elevate privileges locally.
Who is affected: Authorized users of Windows Win32k.
Urgency: Remediation is urgent due to the high severity of the vulnerability.
Action: Update to the latest version to mitigate the vulnerability.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.8
Published: 2026-07-14
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-56176

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-561760.24% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 15% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-56176	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for Windows Win32k Elevation

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

highCVE-2026-58632: Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.nvd · 2026-07-14
mediumCVE-2026-57095: Exposure of sensitive information to an unauthorized actor in Windows Win32K allows an unautho…nvd · 2026-07-14
highCVE-2026-56176: Out-of-bounds read in Windows Win32K - GRFX allows an authorized attacker to elevate privilege…nvd · 2026-07-14
highCVE-2026-50489: Heap-based buffer overflow in Windows Win32K allows an authorized attacker to elevate privileg…nvd · 2026-07-14
highCVE-2026-54986: Heap-based buffer overflow in Windows Win32K allows an authorized attacker to elevate privileg…nvd · 2026-07-14
highCVE-2026-54114: Use after free in Windows Win32K allows an authorized attacker to elevate privileges locally.nvd · 2026-07-14