CVE-1999-0626: rusers information disclosure of valid user accounts

CVE-1999-0626 · Severity: info · CVSS 0 · Published 1997-01-01

The rusers service is an obsolete network protocol that reveals a list of currently logged-in users to anyone on the network. While not a direct software bug, this information disclosure helps attackers perform reconnaissance and identify valid targets for further attacks. Organizations should disable this service as it provides no modern business value and compromises privacy.

Vendors: Sun.

Quick answers

Is CVE-1999-0626 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-1999-0626 being exploited in the wild.
How severe is CVE-1999-0626?
Informational severity, with a CVSS score of 0, published 1 January 1997.
Which products and versions are affected?
unknown rusers.
Is there a fix for CVE-1999-0626?
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-1999-0626 attacked?
It is attacked over the network, in a hosted service.
Am I affected by CVE-1999-0626?
Check whether you run Sun Rpc.Ruserd or Rusers. 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

This entry describes a security weakness in the rusers protocol, which is used to identify users logged into remote machines. By design, the service responds to unauthenticated network queries with a list of active usernames and session details. This constitutes an information disclosure vulnerability that facilitates user enumeration and reconnaissance. Because this is a protocol-level design issue rather than a specific coding error, it is often classified as a configuration or architectural weakness. The recommended remediation is to disable the rusers daemon (rusersd) entirely.

Affected products

  • unknown rusers

Timeline

  • 1997-01-01: disclosed: NVD Published Date

References

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