CVE-2000-0457: Microsoft Internet Information Server

High severity, CVSS 7.5. EPSS: 52.8% chance of exploitation in the next 30 days.

ISM.DLL in IIS 4.0 and 5.0 allows remote attackers to read file contents by requesting the file and appending a large number of encoded spaces (%20) and terminated with a .htr extension, aka the ".HTR File Fragment Reading" or "File Fragment Reading via .HTR" vulnerability.

Affected products

• Microsoft Internet Information Server: version 4.0 only
• Microsoft Internet Information Services: version 5.0 only

Published 2000-05-11. Last modified 2026-06-16.