# CVE-1999-0038: Sun Solaris xlock buffer overflow privilege escalation

Source: https://junglewise.ai/threats/cve-1999-0038-sun-solaris-xlock-buffer-overflow-privilege-escalation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 1997-04-26. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-1999-0038 · Severity: high · CVSS 8.4 · Published 1997-04-26

A security vulnerability exists in the xlock program, a utility used to lock terminal screens on Unix-based systems. A local user with access to the system can exploit this flaw to bypass security restrictions and execute commands with administrative (root) privileges. This could lead to a complete takeover of the affected machine and unauthorized access to all stored data.

## Quick answers

**Is CVE-1999-0038 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-0038 being exploited in the wild.

**How severe is CVE-1999-0038?** High severity, with a CVSS score of 8.4, published 26 April 1997.

**Which products and versions are affected?** Sun Solaris 2.3, 2.4, 2.5, 2.5.1; Sun SunOS 5.3, 5.4, 5.5, 5.5.1.

**Is there a fix for CVE-1999-0038?** 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-1999-0038 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-1999-0038?** Check whether anything you run is named in the advisory. 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 xlock program contains a classic buffer overflow vulnerability (CWE-120) due to insufficient bounds checking on input data. Because xlock often runs with elevated privileges to manage screen locking and authentication, an attacker can provide specially crafted input to overflow a buffer and overwrite memory. This allows a local, unprivileged user to hijack the program's execution flow and execute arbitrary code with root privileges. The vulnerability is exploitable locally without requiring user interaction or prior administrative permissions.

## Affected products

- Sun Solaris 2.3, 2.4, 2.5, 2.5.1
- Sun SunOS 5.3, 5.4, 5.5, 5.5.1

## Timeline

- 1997-04-26: disclosed: Initial publication date in NVD

## References

- [https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0038](https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0038)