All vulnerabilities

Servers and applications

CVE-2000-0457

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.

Severity
High 7.5
Published
11 May 2000
Last changed
16 Jun 2026
Added to UpHeron
21 Oct 2026
Exploit chance
53% in the next 30 daysHigher than 98% of CVEs. EPSS by FIRST, 12 Nov 2026
Attack
Over the network · No login needed
Attacker can
Read some data · Change some data · Slow it down
CVSS vector
AV:N/AC:L/Au:N/C:P/I:P/A:P
Sources
NVD

Affected software

SoftwareAffected versions
Microsoft IISServers and applications · cpe:a:microsoft:internet_information_services
  • Version 5.0

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2000-0457
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2000-0457