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…
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
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.
Affected Products
index servermicrosoftindexing servicemicrosoftinternet information servermicrosoftResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Microsoft Index Server 2.0 / Indexing Service (Windows 2000) - ISAPI Extension Buffer Overflow (3)
by mat · Jun 18, 2001
Microsoft Index Server 2.0 / Indexing Service (Windows 2000) - ISAPI Extension Buffer Overflow (2)
by hsj · Jun 21, 2001
Microsoft Index Server 2.0 / Indexing Service (Windows 2000) - ISAPI Extension Buffer Overflow (PoC)
by Ps0 · Jun 18, 2001
Microsoft IIS 5.0 - IDQ Path Overflow (MS01-033) (Metasploit)
by Metasploit · Jun 15, 2010
Microsoft Index Server 2.0 / Indexing Service (Windows 2000) - ISAPI Extension Buffer Overflow (4)
by blackangels · Jun 18, 2001
Detection & mitigation playbook
Vendor / applianceDetect
Inventory every microsoft index server deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Remediation status
No patch has shipped for CVE-2001-0500 yet — track the microsoft index server advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2001-0500 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2001-0500. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2001-0500 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2001-0500 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.