# CVE-1999-0085: IBM AIX rwhod buffer overflow via long hostname

Source: https://junglewise.ai/threats/cve-1999-0085-ibm-aix-rwhod-buffer-overflow-via-long-hostname  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 1996-08-21. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-1999-0085 · Severity: high · CVSS 7.5 · Published 1996-08-21

A vulnerability exists in the rwhod service, a legacy networking tool used to display who is logged into various machines on a local network. By sending a specially crafted network packet, a remote attacker can crash the service or potentially take control of the affected system. This could lead to unauthorized access to sensitive data or a complete disruption of the server's operations.

Technologies: [Freebsd](https://junglewise.ai/threats/technologies/freebsd), [IBM Aix](https://junglewise.ai/threats/technologies/aix), [Netbsd](https://junglewise.ai/threats/technologies/netbsd). Vendors: [Bsd](https://junglewise.ai/threats/vendors/bsd), [Freebsd](https://junglewise.ai/threats/vendors/freebsd), [IBM](https://junglewise.ai/threats/vendors/ibm), [Netbsd](https://junglewise.ai/threats/vendors/netbsd).

## Quick answers

**Is CVE-1999-0085 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-0085 being exploited in the wild.

**How severe is CVE-1999-0085?** High severity, with a CVSS score of 7.5, published 21 August 1996.

**Which products and versions are affected?** IBM AIX; BSD rwhod.

**Is there a fix for CVE-1999-0085?** 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-1999-0085 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-1999-0085?** Check whether you run Bsd Rwhod, Freebsd, IBM Aix or one of the others listed. 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 rwhod daemon is vulnerable to a classic stack-based buffer overflow. The flaw resides in the processing of incoming UDP packets, specifically when handling the hostname field. An attacker can send a maliciously crafted UDP packet to the rwhod port (typically 513) containing a hostname that exceeds the allocated buffer size. This allows for the overwriting of the stack, potentially leading to arbitrary code execution with the privileges of the rwhod process (often root). The vulnerability is reachable over the network without authentication.

## Affected products

- IBM AIX
- BSD rwhod

## Timeline

- 1996-08-21: disclosed: Vulnerability published in NVD

## References

- [https://exchange.xforce.ibmcloud.com/vulnerabilities/118](https://exchange.xforce.ibmcloud.com/vulnerabilities/118)
- [https://exchange.xforce.ibmcloud.com/vulnerabilities/119](https://exchange.xforce.ibmcloud.com/vulnerabilities/119)

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