CVE-2026-34347

#include <windows.h> #include <stdio.h> // This is a generic PoC structure for a Win32k UAF vulnerability // Actual exploitation requires specific object manipulation and heap grooming void TriggerUAF() { HWND hWnd = CreateWindowExW(0, L"Button", L"UAF_Test", 0, 0, 0, 0, 0, NULL, NULL, NULL, NULL); if (!hWnd) return; // Step 1: Allocate and set up the vulnerable object // SetClassLongPtr(hWnd, GCLP_WNDPROC, (LONG_PTR)MaliciousCallback); // Step 2: Trigger the free operation inside the kernel // SendMessage(hWnd, WM_CLOSE, 0, 0); // Step 3: Reallocate the freed memory with controlled data // HeapSpray(); // Step 4: Trigger the use-after-free to gain code execution // SendMessage(hWnd, WM_PAINT, 0, 0); DestroyWindow(hWnd); } int main() { printf("[+] Attempting to trigger CVE-2026-34347 PoC...\n"); TriggerUAF(); printf("[+] Exploit logic finished.\n"); return 0; }

{"cve": {"id": "CVE-2026-34347", "sourceIdentifier": "[email protected]", "published": "2026-05-12T18:17:09.360", "lastModified": "2026-05-14T17:45:54.743", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Use after free in Windows Win32K - GRFX allows an authorized attacker to elevate privileges locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.0, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.0, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-416"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "D48FE1A3-FD94-469C-87EA-AA7B4AAC6B86"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "027462CD-8FA3-4C9F-8778-5AB3F4CDB5B1"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.17763.8755", "matchCriteriaId": "94017187-8A34-41BB-A49E-0FA6986E8CB8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.17763.8755", "matchCriteriaId": "BB81D249-7566-44B7-914C-A3674CE87AFB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.19044.7291", "matchCriteriaId": "92E25E15-66FF-45E3-A044-88A7CFDEA9DF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19044.7291", "matchCriteriaId": "0D04D4AA-D1A5-45D4-A27A-F80D3F6171AF"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.19044.7291", "matchCriteriaId": "12B4D343-5326-4CF2-913D-F642C34B458A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.19045.7291", "matchCriteriaId": "6BB3BCA4-519F-4BAB-B7C7-9E3BBCE5A6AB"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19045.7291", "matchCriteriaId": "65466E7E-0BDC-4ECC-AE5F-2E4B8615D205"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.19045.7291", "matchCriteriaId": "A722684E-1073-4076-82AE-3235AA1C4C9F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.22631.7079", "matchCriteriaId": "D039A905-2FE4-4A10-85BF-175947E6A017"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.22631.7079", "matchCriteriaId": "4904DDBD-B183-4AA2-ABD6-47BAF1A28861"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.26100.8390", "matchCriteriaId": "048AD3CD-DD62-4B62-9302-61779D998B4A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.26100.8390", "matchCriteriaId": "3682F4DD-0870-4E39-B75E-649C89BB1E08"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.26200.8390", "matchCriteriaId": "C2C93D38-DFD7-4DE1-95B8-6D73E4A545D6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.26200.8390", "matchCriteriaId": "05EB89A0-2ADD-4B67-A644-41FE1DE69E4A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.28000.2113", "matchCriteriaId": "D45A5D2F-E058-4033-B184-BAE224FC1CEA"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.28000.2113", "matchCriteriaId": "5127F350-9271-4B74-84E0-D7E5D2D5640E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*", "matchCriteriaId": "A7DF96F8-BA6A-4780-9CA3-F719B3F81074"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2012:r2:*:*:*:*:*:*:*", "matchCriteriaId": "DB18C4CE-5917-401E-ACF7-2747084FD36E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "71D026B8-B196-4369-9AB3-5FCA ... 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