CVE-2001-0500

CVE-2001-0500 is a critical-severity vulnerability in Microsoft Index Server with a CVSS 2.0 base score of 10.0. Its EPSS exploit-prediction score of 97% places it in the 100th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

Buffer overflow in ISAPI extension (idq.dll) in Index Server 2.0 and Indexing Service 2000 in IIS 6.0 beta and earlier allows remote attackers to execute arbitrary commands via a long argument to Internet Data Administration (.ida) and Internet Data Query (.idq) files such as default.ida, as commonly exploited by Code Red.

Frequently asked questions

What is CVE-2001-0500?
Buffer overflow in ISAPI extension (idq.dll) in Index Server 2.0 and Indexing Service 2000 in IIS 6.0 beta and earlier allows remote attackers to execute arbitrary commands via a long argument to Internet Data Administration (.ida) and Internet Data Query (.idq) files such as default.ida, as commonly exploited by Code Red.
How severe is CVE-2001-0500?
CVE-2001-0500 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-2001-0500 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 97% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2001-0500?
CVE-2001-0500 primarily affects Microsoft Index Server. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2001-0500?
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-2001-0500 published?
CVE-2001-0500 was published on 2001-07-21 and last updated on 2026-06-16.

References

Affected products (3)

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