# CVE-1999-0265: Microsoft Windows NT Denial of Service via ICMP Redirect

Source: https://junglewise.ai/threats/cve-1999-0265-microsoft-windows-nt-denial-of-service-via-icmp-redirect  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 1997-01-01. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-1999-0265 · Severity: medium · CVSS 5 · Published 1997-01-01

A vulnerability in the way certain operating systems handle network routing update messages can allow an attacker to remotely crash or freeze a computer. This affects the availability of the system, potentially causing service outages or data loss if the system is not restarted. The issue stems from how the system processes Internet Control Message Protocol (ICMP) redirect packets.

Technologies: [Microsoft Windows Nt](https://junglewise.ai/threats/technologies/windows-nt), [Novell Netware](https://junglewise.ai/threats/technologies/netware). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft), [Novell](https://junglewise.ai/threats/vendors/novell).

## Quick answers

**Is CVE-1999-0265 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-0265 being exploited in the wild.

**How severe is CVE-1999-0265?** Medium severity, with a CVSS score of 5, published 1 January 1997.

**Which products and versions are affected?** Microsoft Windows NT.

**Is there a fix for CVE-1999-0265?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-1999-0265 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-1999-0265?** Check whether you run Microsoft Windows Nt, Microware Os-9 or Novell Netware. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a denial-of-service flaw resulting from improper input validation (CWE-20) of ICMP redirect messages. An unauthenticated remote attacker can send specially crafted ICMP redirect packets to a target host. If the host's network stack does not correctly validate these messages, it can lead to a system crash or a kernel-level lockup. This issue was historically associated with Microsoft Windows NT and other legacy network stacks that processed ICMP redirects without sufficient verification of the source or packet integrity. Patch information is referenced in legacy Microsoft Knowledge Base article Q154174.

## Affected products

- Microsoft Windows NT

## Timeline

- 1997-01-01: disclosed
- 1997-01-01: advisory

## References

- [http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ154174](http://support.microsoft.com/default.aspx?scid=kb%3B%5BLN%5D%3BQ154174)

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