Security Vulnerability Report
中文
CVE-2026-20835 CVSS 5.5 MEDIUM

CVE-2026-20835

Published: 2026-01-13 18:16:12
Last Modified: 2026-01-15 15:05:29

Description

Out-of-bounds read in Capability Access Management Service (camsvc) allows an authorized attacker to disclose information locally.

CVSS Details

CVSS Score
5.5
Severity
MEDIUM
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Configurations (Affected Products)

cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:* - VULNERABLE
Windows 10 Version 1809 for 32-bit Systems
Windows 10 Version 1809 for x64-based Systems
Windows 10 Version 1809 for ARM64-based Systems
Windows 10 Version 1903 for 32-bit Systems
Windows 10 Version 1903 for x64-based Systems
Windows 10 Version 1903 for ARM64-based Systems
Windows 10 Version 1909 for 32-bit Systems
Windows 10 Version 1909 for x64-based Systems
Windows 10 Version 1909 for ARM64-based Systems
Windows 10 Version 2004 for 32-bit Systems
Windows 10 Version 2004 for x64-based Systems
Windows 10 Version 2004 for ARM64-based Systems
Windows Server 2019
Windows Server, version 1903
Windows Server, version 1909
Windows Server, version 2004

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
# CVE-2026-20835 PoC - Out-of-bounds Read in camsvc # This PoC demonstrates the vulnerability pattern (for educational purposes only) import ctypes from ctypes import wintypes import struct # Windows API definitions kernel32 = ctypes.windll.kernel32 ntdll = ctypes.windll.ntdll # Define necessary structures and constants class UNICODE_STRING(ctypes.Structure): _fields_ = [ ("Length", wintypes.USHORT), ("MaximumLength", wintypes.USHORT), ("Buffer", ctypes.c_wchar_p) ] # Open camsvc service handle scm_handle = kernel32.OpenSCManagerW(None, None, 0xF003F) if not scm_handle: print("[-] Failed to open Service Control Manager") exit(1) # Open camsvc service service_handle = kernel32.OpenServiceW(scm_handle, "camsvc", 0xF01FF) if not service_handle: print("[-] Failed to open camsvc service") kernel32.CloseServiceHandle(scm_handle) exit(1) print("[+] camsvc service handle obtained successfully") print("[+] Triggering potential out-of-bounds read condition...") # The actual exploitation requires specific malformed requests to camsvc # This PoC demonstrates the pattern - actual exploit needs further research # Cleanup kernel32.CloseServiceHandle(service_handle) kernel32.CloseServiceHandle(scm_handle) print("[+] Note: This is a proof-of-concept demonstrating the attack surface") print("[+] Actual exploitation requires deeper analysis of camsvc interface")

References

Raw JSON Data

JSON
{"cve": {"id": "CVE-2026-20835", "sourceIdentifier": "[email protected]", "published": "2026-01-13T18:16:11.660", "lastModified": "2026-01-15T15:05:28.833", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Out-of-bounds read in Capability Access Management Service (camsvc) allows an authorized attacker to disclose information locally."}, {"lang": "es", "value": "Lectura fuera de límites en el Servicio de Gestión de Acceso a Capacidades (camsvc) 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:L/UI:N/S:U/C:H/I:N/A:N", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-125"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"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_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-2026-20835", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}