Windows NtOperating system · Microsoft

CVE-1999-1365

HIGH · 7.2 CVSS v2.0 Published 1999-06-28
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
77/100
Remediation priority · High
No privileges Zero-click

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
Windows NT searches a user's home directory (%systemroot% by default) before other directories to find critical programs such as NDDEAGNT.EXE, EXPLORER.EXE, USERINIT.EXE or TASKMGR.EXE, which could allow local users to bypass access restrictions or gain privileges by placing a Trojan horse program into the root directory, which is writable by default.

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

Windows NT has a path search order vulnerability where it searches the user's home directory (%systemroot% by default) before system directories when locating critical executables such as NDDEAGNT.EXE, EXPLORER.EXE, USERINIT.EXE, and TASKMGR.EXE. Since the root directory is writable by default, local users can place Trojan horse versions of these programs there, causing them to be executed with elevated privileges instead of the legitimate system binaries.

MitigationThis vulnerability affects legacy Windows NT systems and was addressed in subsequent Windows versions. Organizations should ensure they are not running unsupported Windows NT installations, verify that system root directories have restrictive permissions, and upgrade to supported operating systems if applicable.

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 NtOperating 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
Local
Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete

AV:L/AC:L/Au:N/C:C/I:C/A:C

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. Confirm Windows NT version
    Run 'winver' or check system properties to identify the operating system. If the OS is Windows NT (any version), this vulnerability may apply.
    Affected if Operating system is Windows NT (any version)
  2. Check system root directory permissions
    Use 'cacls C:\' (or the system root drive) to list permissions on the root directory. Verify if standard users or the Everyone group have Write permissions.
    Affected if Users other than Administrators have Write or Full Control permissions on the system root directory
  3. Search for vulnerable executables in system root
    Run 'dir C:\NDDEAGNT.EXE C:\EXPLORER.EXE C:\USERINIT.EXE C:\TASKMGR.EXE' (substituting the actual system root drive) to check if any of these critical executables exist in the root directory.
    Affected if Any of NDDEAGNT.EXE, EXPLORER.EXE, USERINIT.EXE, or TASKMGR.EXE are present in the system root directory
  4. Examine PATH environment variable order
    Run 'echo %PATH%' and verify if the system root directory (typically C:\) appears early in the PATH, before system directories like C:\WINNT\System32.
    Affected if System root directory appears before system directories in the PATH variable

A system is affected if it runs Windows NT and has writable system root permissions that could allow placement of Trojan executables that Windows NT would execute before the legitimate system binaries.

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

This vulnerability affects legacy Windows NT systems and was addressed in subsequent Windows versions. Organizations should ensure they are not running unsupported Windows NT installations, verify that system root directories have restrictive permissions, and upgrade to supported operating systems if applicable.

Fix this in Windows Nt Scoped from the published advisory
  • Consultation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
4.0 hours of engineering $750
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,200.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-1999-1365 — 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-1999-1365 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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