CVE-1999-1087

High CVSS 7.5

Published 1999-12-31 · last changed 2026-06-16

The fix

We hold no Microsoft remediation data for CVE-1999-1087, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.

What it is

Internet Explorer 4 treats a 32-bit number ("dotless IP address") in the a URL as the hostname instead of an IP address, which causes IE to apply Local Intranet Zone settings to the resulting web page, allowing remote malicious web servers to conduct unauthorized activities by using URLs that contain the dotless IP address for their server.

Sources

NVD record for CVE-1999-1087

CVSS vector: AV:N/AC:L/Au:N/C:P/I:P/A:P