# CVE-1999-0628: BSD rwhod information disclosure of machine and user status

Source: https://junglewise.ai/threats/cve-1999-0628-bsd-rwhod-information-disclosure-of-machine-and-user-status  
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-1999-0628 · Severity: medium · CVSS 5 · Published 1997-07-01

The rwho/rwhod service is an older networking utility used to display information about users logged into other machines on a local network. When this service is active, it automatically broadcasts system status and user activity, which can be intercepted by unauthorized parties. This allows an attacker to perform reconnaissance, identifying active users and system uptime, which could be used to plan further targeted attacks.

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

## Quick answers

**Is CVE-1999-0628 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-0628 being exploited in the wild.

**How severe is CVE-1999-0628?** Medium severity, with a CVSS score of 5, published 1 July 1997.

**Which products and versions are affected?** BSD-derived systems rwhod daemon.

**Is there a fix for CVE-1999-0628?** 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-1999-0628 attacked?** It is attacked over the network, in an operating system.

**Am I affected by CVE-1999-0628?** Check whether you run Freebsd, IBM Aix, Linux Kernel 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 maintains a database of the status of other machines on a local network by broadcasting and receiving UDP packets. This protocol lacks authentication and encryption, allowing any network-adjacent observer to collect sensitive information such as who is logged in, how long they have been idle, and system load averages. This is classified as an information disclosure vulnerability. To mitigate this risk, the rwhod service should be disabled on systems where it is not strictly required for legacy operations.

## Affected products

- BSD-derived systems rwhod daemon

## Timeline

- 1997-07-01: disclosed: NVD published date

## References

- [https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0628](https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0628)

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