# CVE-1999-0195: Generic RPC portmapper denial of service via source IP spoofing

Source: https://junglewise.ai/threats/cve-1999-0195-generic-rpc-portmapper-denial-of-service-via-source-ip-spoofing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 1997-07-01. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-1999-0195 · Severity: medium · CVSS 5 · Published 1997-07-01

A vulnerability in the RPC portmapper service allows remote attackers to disrupt network services. By spoofing their identity, attackers can unregister legitimate services or register fake ones, leading to a denial of service for users and applications that rely on these network connections. This can result in the failure of critical system functions and internal communication tools.

Technologies: [Linux Kernel](https://junglewise.ai/threats/technologies/kernel), [Sgi Irix](https://junglewise.ai/threats/technologies/irix). Vendors: [Linux](https://junglewise.ai/threats/vendors/linux), [Sgi](https://junglewise.ai/threats/vendors/sgi).

## Quick answers

**Is CVE-1999-0195 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-0195 being exploited in the wild.

**How severe is CVE-1999-0195?** Medium severity, with a CVSS score of 5, published 1 July 1997.

**Which products and versions are affected?** Generic RPC portmapper.

**Is there a fix for CVE-1999-0195?** 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-1999-0195 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-1999-0195?** Check whether you run Linux Kernel, Sgi Irix or RPC portmapper. 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 RPC portmapper service contains a vulnerability that allows for unauthorized registration or unregistration of RPC services. An attacker can exploit this by sending requests with a spoofed source IP address, such as the localhost address (127.0.0.1), to bypass simple source-based authentication checks. This allows the attacker to unregister legitimate services, causing a denial of service, or to register malicious services to intercept or spoof RPC traffic. The attack is reachable over the network and does not require authentication. This issue is historically significant in early Unix-like operating systems and network service implementations.

## Affected products

- Generic RPC portmapper

## Timeline

- 1997-07-01: disclosed

## References

- [https://www.cve.org/CVERecord?id=CVE-1999-0195](https://www.cve.org/CVERecord?id=CVE-1999-0195)

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