CVE-1999-0994: Medium severity Microsoft Windows NT vulnerability

Published Dec 16, 1999
·
Updated

Windows NT with SYSKEY reuses the keystream that is used for encrypting SAM password hashes, allowing an attacker to crack passwords.

Affected Software

4 affected components
Microsoft Windows NT=4.0
Microsoft Windows NT=4.0
Microsoft Windows NT=4.0-sp1
Microsoft Windows NT=4.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Configuration

    Disable SYSKEY on affected Windows NT systems to prevent reuse of the keystream used to encrypt SAM password hashes.

    Microsoft Windows NT (SAM/SYSKEY) SYSKEY = disabled
  2. Operational

    Rotate all account passwords stored in the SAM on affected Windows NT systems after addressing SYSKEY to ensure any potentially compromised password hashes are changed.

Event History

Dec 16, 1999
CVE Published
05:00 AM
Data Sourced
via NVD·05:00 AM
DescriptionSeverityWeaknessAffected Software
Jan 18, 2000
CVE Published
via MITRE·10:00 AM
Data Sourced
via MITRE·10:00 AM
Description

Frequently Asked Questions

1

What is the severity of CVE-1999-0994?

CVE-1999-0994 is considered to be of high severity due to the potential for password cracking.

2

How do I fix CVE-1999-0994?

To fix CVE-1999-0994, upgrade to a later version of Windows that does not utilize SYSKEY in this manner.

3

What versions of Windows NT are affected by CVE-1999-0994?

CVE-1999-0994 affects Windows NT 4.0 and its service packs.

4

What exploitation methods are possible with CVE-1999-0994?

An attacker can exploit CVE-1999-0994 by guessing or cracking weak passwords due to the reused keystream.

5

Is there a workaround for CVE-1999-0994 if upgrading is not possible?

A possible workaround for CVE-1999-0994 is to enforce strong password policies to mitigate the risk of password cracking.

Contact

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