# CVE-1999-0030: SGI IRIX root privilege escalation via buffer overflow in xlock

Source: https://junglewise.ai/threats/cve-1999-0030-sgi-irix-root-privilege-escalation-via-buffer-overflow-in-xlock  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 1997-07-16. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-1999-0030 · Severity: high · CVSS 7.2 · Published 1997-07-16

A security vulnerability exists in the xlock utility on SGI IRIX operating systems, which is used to lock a user's display. A local user can exploit this flaw to bypass security restrictions and gain full administrative (root) control over the system. This could lead to a complete compromise of the machine, including unauthorized access to all data and system settings.

Technologies: [Sgi Irix](https://junglewise.ai/threats/technologies/irix). Vendors: [Sgi](https://junglewise.ai/threats/vendors/sgi).

## Quick answers

**Is CVE-1999-0030 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-0030 being exploited in the wild.

**How severe is CVE-1999-0030?** High severity, with a CVSS score of 7.2, published 16 July 1997.

**Which products and versions are affected?** SGI IRIX.

**Is there a fix for CVE-1999-0030?** 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-1999-0030 attacked?** It is attacked with local access, in an operating system.

**Am I affected by CVE-1999-0030?** Check whether you run Sgi Irix. 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 utility in SGI IRIX contains a buffer overflow vulnerability. By providing specially crafted input to the command, a local attacker can overflow a buffer and execute arbitrary code with elevated privileges. Because xlock is typically installed with setuid root permissions to manage screen locking and authentication, successful exploitation allows a non-privileged local user to gain full root access to the operating system. The vulnerability is triggered locally and does not require prior administrative authentication.

## Affected products

- SGI IRIX

## Timeline

- 1997-07-16: disclosed

## References

- [https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0030](https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0030)

## Related threats

- [Vulnerability in (1) diskperf and (2) diskalign in IRIX 6.4 allows local attacker to create arbitrary root owned…](https://junglewise.ai/threats/cve-1999-1492-vulnerability-in-1-diskperf-and-2-diskalign-in-irix-6-4-allows)
- [Vulnerability in (1) diskalign and (2) diskperf in IRIX 6.4 patches 2291 and 2848 allow a local user to create…](https://junglewise.ai/threats/cve-1999-1039-vulnerability-in-1-diskalign-and-2-diskperf-in-irix-6-4-patches)
- [SGI IRIX buffer overflow in xterm and Xaw](https://junglewise.ai/threats/cve-1999-0126-sgi-irix-buffer-overflow-in-xterm-and-xaw)
- [SGI IRIX buffer overflow in printers program](https://junglewise.ai/threats/cve-1999-0108-sgi-irix-buffer-overflow-in-printers-program)
- [SGI IRIX command injection in ipxchk and ipxlink](https://junglewise.ai/threats/cve-1999-1501-sgi-irix-command-injection-in-ipxchk-and-ipxlink)