Security Vulnerability Report
中文
CVE-2026-34339 CVSS 5.5 MEDIUM

CVE-2026-34339

Published: 2026-05-12 18:17:08
Last Modified: 2026-05-14 15:14:02

Description

Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an authorized attacker to deny service 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:N/I:N/A:H

Configurations (Affected Products)

cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x64:* - VULNERABLE
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:x86:* - VULNERABLE
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:* - VULNERABLE
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:* - VULNERABLE
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:arm64:* - VULNERABLE
Windows 10 (所有受支持版本)
Windows 11 (所有受支持版本)
Windows Server 2019/2022 (具体版本请参考微软安全公告)

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import ldap3 # PoC for CVE-2026-34339 (Conceptual) # This script attempts to trigger the Null Pointer Dereference # by sending a malformed request to the local LDAP service. server = 'ldap://localhost' user = 'CN=Attacker,CN=Users,DC=domain,DC=com' password = 'Password123' try: # Establish connection conn = ldap3.Connection(server, user=user, password=password, auto_bind=True) print("[+] Connected to LDAP server") # Malformed control or filter to trigger the vulnerability # Note: The specific malformed packet structure depends on the actual vulnerability details. # This is a placeholder demonstrating the trigger mechanism. malformed_filter = '(objectClass=*)' # Hypothetical trigger # Send search request conn.search(search_base='', search_filter=malformed_filter, attributes=['*']) print("[+] Packet sent, checking service status...") except Exception as e: print(f"[-] Error occurred: {e}") print("[!] Service might have crashed due to Null Pointer Dereference.")

References

Raw JSON Data

JSON
{"cve": {"id": "CVE-2026-34339", "sourceIdentifier": "[email protected]", "published": "2026-05-12T18:17:08.130", "lastModified": "2026-05-14T15:14:01.550", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Null pointer dereference in Windows LDAP - Lightweight Directory Access Protocol allows an authorized attacker to deny service locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-476"}]}], "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_2016:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.14393.9140", "matchCriteriaId": "71D026B8-B196-4369-9AB3-5FCA21E8AA36"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*", "versionEndExcluding": "10.0.17763.8755", "matchCriteriaId": "C1926806-B15D-4AF1-967A-7ADA71FF74DC"}, {"vulnerable": true, "criteria": "cpe:2.3:o:microsoft:windows_s ... 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