CVE-2026-83939
CVE-2026-83939 is a high-severity vulnerability in Microsoft Windows 11 26h1 with a CVSS 3.x base score of 8.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-822.
Key facts
- Severity: High (CVSS 3.x base score 8.2)
- EPSS exploit prediction: 0% (26th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-822
- Affected product: Microsoft Windows 11 26h1
- Published:
- Last modified:
Description
Untrusted pointer dereference in Windows Secure Kernel Mode allows an authorized attacker to elevate privileges locally.
Frequently asked questions
- What is CVE-2026-83939?
- Untrusted pointer dereference in Windows Secure Kernel Mode allows an authorized attacker to elevate privileges locally.
- How severe is CVE-2026-83939?
- CVE-2026-83939 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-83939 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-83939?
- CVE-2026-83939 primarily affects Microsoft Windows 11 26h1. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-83939?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2026-83939 published?
- CVE-2026-83939 was published on 2026-09-08 and last updated on 2026-09-10.
References
Affected products (2)
- cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*
- cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*
More vulnerabilities in Microsoft Windows 11 26h1
- CVE-2026-57092 — Critical (CVSS 9.9): Use after free in Windows VMSwitch allows an authorized attacker to elevate privileges over a network.
- CVE-2026-77493 — Critical (CVSS 9.8): Double free in Microsoft Graphics Component allows an unauthorized attacker to execute code over a network.
- CVE-2026-73009 — Critical (CVSS 9.8): Use after free in Windows Secure Socket Tunneling Protocol (SSTP) allows an unauthorized attacker to execute code over…
- CVE-2026-72983 — Critical (CVSS 9.8): Use after free in Windows Internet Connection Sharing (ICS) allows an unauthorized attacker to execute code over a…
- CVE-2026-72982 — Critical (CVSS 9.8): Stack-based buffer overflow in Windows Netlogon allows an unauthorized attacker to execute code over a network.
- CVE-2026-70296 — Critical (CVSS 9.8): Out-of-bounds write in Windows Imaging Component allows an unauthorized attacker to execute code over a network.
All CVEs affecting Microsoft Windows 11 26h1 →
Other CWE-822 vulnerabilities
- CVE-2026-103764 — Critical (CVSS 9.8): Mooncake transfer engine before 0.3.13 contains an untrusted pointer dereference in ServerSession::readHeader that…
- CVE-2025-50165 — Critical (CVSS 9.8): Untrusted pointer dereference in Microsoft Graphics Component allows an unauthorized attacker to execute code over a…
- CVE-2023-1437 — Critical (CVSS 9.8): All versions prior to 9.1.4 of Advantech WebAccess/SCADA are vulnerable to use of untrusted pointers. The RPC arguments…
- CVE-2026-48137 — Critical (CVSS 9.1): There is an untrusted pointer dereference vulnerability in the NI grpc-device sideband streaming API that may allow an…
- CVE-2025-4993 — Critical (CVSS 9.1): Untrusted Pointer Dereference vulnerability in RTI Connext Professional (Core Libraries) allows Pointer Manipulation.…
- CVE-2025-1255 — Critical (CVSS 9.1): Untrusted Pointer Dereference vulnerability in RTI Connext Professional (Core Libraries) allows Pointer Manipulation.…