CVE-1999-0994
Status: ModifiedMedium (5)—
Windows NT with SYSKEY reuses the keystream that is used for encrypting SAM password hashes, allowing an attacker to crack passwords.
CVSS
- Version: 2.0
- Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N
- Base score: 5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 7.14%
- Percentile among all scored CVEs: 94
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- CWE-255
References
- http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ248183
- http://www.securityfocus.com/bid/873
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/1999/ms99-056
- http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ248183
- http://www.securityfocus.com/bid/873
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/1999/ms99-056
Raw JSON (NVD)
Show
{
"id": "CVE-1999-0994",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 5,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "NONE",
"confidentialityImpact": "PARTIAL"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
]
},
"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "1999-12-16T05:00:00.000",
"references": [
{
"url": "http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ248183",
"source": "cve@mitre.org"
},
{
"url": "http://www.securityfocus.com/bid/873",
"source": "cve@mitre.org"
},
{
"url": "https://docs.microsoft.com/en-us/security-updates/securitybulletins/1999/ms99-056",
"source": "cve@mitre.org"
},
{
"url": "http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ248183",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://www.securityfocus.com/bid/873",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://docs.microsoft.com/en-us/security-updates/securitybulletins/1999/ms99-056",
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-255"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Windows NT with SYSKEY reuses the keystream that is used for encrypting SAM password hashes, allowing an attacker to crack passwords."
}
],
"lastModified": "2026-06-16T21:49:28.960",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:microsoft:windows_nt:4.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "E53CDA8E-50A8-4509-B070-CCA5604FFB21"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_nt:4.0:*:server:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "7C5FCE82-1E2F-49B9-B504-8C03F2BCF296"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_nt:4.0:*:terminal_server:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "6E7E6AD3-5418-4FEA-84B5-833059CA880D"
},
{
"criteria": "cpe:2.3:o:microsoft:windows_nt:4.0:sp1:enterprise:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "BBD9C514-5AF7-4849-A535-F0F3C9339051"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "cve@mitre.org"
}