How severe is CVE-1999-1376?

CVE-1999-1376 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-1999-1376 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 24% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-1376?

CVE-1999-1376 affects Microsoft Internet Information Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-1999-1376?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-1999-1376 published?

CVE-1999-1376 was published on 1999-01-14 and last updated on 2026-06-16.

CVE-1999-1376

CVE-1999-1376 is a critical-severity vulnerability in Microsoft Internet Information Server with a CVSS 2.0 base score of 10.0. Its EPSS exploit-prediction score of 24% places it in the 98th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 24% (98th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft Internet Information Server
Published: 1999-01-14
Last modified: 2026-06-16

Description

Buffer overflow in fpcount.exe in IIS 4.0 with FrontPage Server Extensions allows remote attackers to execute arbitrary commands.

Frequently asked questions

What is CVE-1999-1376?: Buffer overflow in fpcount.exe in IIS 4.0 with FrontPage Server Extensions allows remote attackers to execute arbitrary commands.
How severe is CVE-1999-1376?: CVE-1999-1376 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-1999-1376 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 24% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-1376?: CVE-1999-1376 affects Microsoft Internet Information Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-1999-1376?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-1999-1376 published?: CVE-1999-1376 was published on 1999-01-14 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:microsoft:internet_information_server:4.0:*:*:*:*:*:*:*

More vulnerabilities in Microsoft Internet Information Server

CVE-2008-0075 — Critical (CVSS 10.0): Unspecified vulnerability in Microsoft Internet Information Services (IIS) 5.1 through 6.0 allows remote attackers to…
CVE-2001-0500 — Critical (CVSS 10.0): Buffer overflow in ISAPI extension (idq.dll) in Index Server 2.0 and Indexing Service 2000 in IIS 6.0 beta and earlier…
CVE-1999-1011 — Critical (CVSS 10.0): The Remote Data Service (RDS) DataFactory component of Microsoft Data Access Components (MDAC) in IIS 3.x and 4.x…
CVE-1999-0874 — Critical (CVSS 10.0): Buffer overflow in IIS 4.0 allows remote attackers to cause a denial of service via a malformed request for files with…
CVE-1999-0407 — Critical (CVSS 10.0): By default, IIS 4.0 has a virtual directory /IISADMPWD which contains files that can be used as proxies for brute force…
CVE-2009-3023 — Critical (CVSS 9.0): Buffer overflow in the FTP Service in Microsoft Internet Information Services (IIS) 5.0 through 6.0 allows remote…

All CVEs affecting Microsoft Internet Information Server →