Windows 10Operating system · Microsoft

CVE-2016-3352

HIGH · 8.8 CVSS v3.0 Published 2016-09-14
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
95/100
Remediation priority · Urgent
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Microsoft Windows 8.1, Windows RT 8.1, and Windows 10 Gold, 1511, and 1607 do not properly check NTLM SSO requests for MSA logins, which makes it easier for remote attackers to determine passwords via a brute-force attack on NTLM password hashes, aka "Microsoft Information Disclosure Vulnerability."

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

This vulnerability in Windows 8.1, RT 8.1, and Windows 10 versions allows remote attackers to bypass proper validation of NTLM SSO requests for Microsoft Account (MSA) logins. The insufficient checking enables brute-force attacks against NTLM password hashes, potentially exposing user credentials.

MitigationApply Microsoft security updates for CVE-2016-3352 to affected Windows versions. Additionally, consider implementing account lockout policies and NTLM session restrictions to limit brute-force attack viability.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Windows 10Operating system
Affected:all versions= 1511= 1607
Windows 8.1Operating system
Affected:all versions
Windows Rt 8.1Operating system
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Windows version
    Run 'winver' from the command prompt or check System Properties (right-click This PC > Properties) to determine the exact Windows version
    Affected if The system is running Windows 8.1, Windows RT 8.1, or any version of Windows 10 (including 1511 and 1607)
  2. Verify NTLM authentication is in use
    Open Local Group Policy Editor (gpedit.msc) and navigate to Computer Configuration > Windows Settings > Security Settings > Local Policies > Security Options > 'Network security: LAN Manager authentication level'. Check the current setting.
    Affected if The authentication level is set to allow NTLM responses (options like 'Send LM & NTLM responses' or 'Send LM & NTLM - use NTLMv2 session security if negotiated') rather than restricting to NTLMv2 only or rejecting NTLM entirely
  3. Confirm Microsoft Account login is enabled
    Open Settings > Accounts > Your email and accounts, or run 'netplwiz', to verify if a Microsoft Account (MSA) is linked to user login on this system
    Affected if A Microsoft Account is configured for Windows sign-in on this machine

The environment is affected if the system runs Windows 8.1, RT 8.1, or Windows 10, has NTLM authentication enabled, and has a Microsoft Account configured for login.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply Microsoft security updates for CVE-2016-3352 to affected Windows versions. Additionally, consider implementing account lockout policies and NTLM session restrictions to limit brute-force attack viability.

Fix this in Windows 10 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2016-3352 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2016-3352 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data