CVE-1999-0995
CVE-1999-0995 is a high-severity vulnerability in Microsoft Windows Nt with a CVSS 2.0 base score of 7.8. Its EPSS exploit-prediction score of 22% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.
Key facts
- Severity: High (CVSS 2.0 base score 7.8)
- EPSS exploit prediction: 22% (97th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Microsoft Windows Nt
- Published:
- Last modified:
Description
Windows NT Local Security Authority (LSA) allows remote attackers to cause a denial of service via malformed arguments to the LsaLookupSids function which looks up the SID, aka "Malformed Security Identifier Request."
Frequently asked questions
- What is CVE-1999-0995?
- Windows NT Local Security Authority (LSA) allows remote attackers to cause a denial of service via malformed arguments to the LsaLookupSids function which looks up the SID, aka "Malformed Security Identifier Request."
- How severe is CVE-1999-0995?
- CVE-1999-0995 has a CVSS 2.0 base score of 7.8, rated high severity.
- Is CVE-1999-0995 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 22% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-1999-0995?
- CVE-1999-0995 primarily affects Microsoft Windows Nt. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-1999-0995?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-1999-0995 published?
- CVE-1999-0995 was published on 1999-12-16 and last updated on 2026-06-16.
References
- http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ248185
- http://www.securityfocus.com/bid/875
- https://docs.microsoft.com/en-us/security-updates/securitybulletins/1999/ms99-057
Affected products (4)
- cpe:2.3:o:microsoft:windows_nt:4.0:*:*:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_nt:4.0:*:server:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_nt:4.0:*:terminal_server:*:*:*:*:*
- cpe:2.3:o:microsoft:windows_nt:4.0:sp1:enterprise:*:*:*:*:*
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