CVE-2001-0664

CVE-2001-0664 is a high-severity vulnerability in Microsoft Internet Explorer with a CVSS 2.0 base score of 7.5. Its EPSS exploit-prediction score of 18% places it in the 97th percentile, indicating an elevated likelihood of exploitation.

Key facts

Description

Internet Explorer 5.5 and 5.01 allows remote attackers to bypass security restrictions via malformed URLs that contain dotless IP addresses, which causes Internet Explorer to process the page in the Intranet Zone, which may have fewer security restrictions, aka the "Zone Spoofing vulnerability."

Frequently asked questions

What is CVE-2001-0664?
Internet Explorer 5.5 and 5.01 allows remote attackers to bypass security restrictions via malformed URLs that contain dotless IP addresses, which causes Internet Explorer to process the page in the Intranet Zone, which may have fewer security restrictions, aka the "Zone Spoofing vulnerability."
How severe is CVE-2001-0664?
CVE-2001-0664 has a CVSS 2.0 base score of 7.5, rated high severity.
Is CVE-2001-0664 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 18% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2001-0664?
CVE-2001-0664 primarily affects Microsoft Internet Explorer. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2001-0664?
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-2001-0664 published?
CVE-2001-0664 was published on 2001-10-30 and last updated on 2026-06-16.

References

Affected products (2)

More vulnerabilities in Microsoft Internet Explorer

All CVEs affecting Microsoft Internet Explorer →