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CERT Coordination Center

SCO OpenServer/UnixWare vi creates temporary files insecurely

Vulnerability Note VU#747736

Original Release Date: 2001-10-09 | Last Revised: 2001-10-09


The implementation of vi, a text editor, provided with SCO Openunix creates insecure temporary files with predictable names. Using a symbolic link attack, an intruder can overwrite any file writable by the user of vi.


vi is a screen-oriented text editor. The implementation distributed with SCO Openunix creates temporary files in the world-writable directory /tmp with predictable names, and fails to check for prior ownership and protection of these files.


By creating symbolic links named for the files that vi creates, an intruder may overwrite any file writable by the user of vi. Since the intruder cannot control the content of the overwritten files, it does not seem likely that an increase in privilege will result.


Apply vendor patches; see the Systems Affected section below.

Vendor Information


SCO Affected

Notified:  September 18, 2001 Updated: September 20, 2001



Vendor Statement

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.


The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

CVSS Metrics

Group Score Vector



This vulnerability was first reported by Richard Johnson.

This document was last edited by Tim Shimeall

Other Information

CVE IDs: CVE-2001-0627
Severity Metric: 1.01
Date Public: 2001-05-31
Date First Published: 2001-10-09
Date Last Updated: 2001-10-09 15:41 UTC
Document Revision: 13

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