search menu icon-carat-right cmu-wordmark

CERT Coordination Center

ISC inn creates temporary files insecurely

Vulnerability Note VU#964488

Original Release Date: 2001-09-27 | Last Revised: 2001-09-27

Overview

inn, a network news agent, may be configured on some operating systems to use a publically-writeable directory for its temporary files. This may be exploited to gain access to the news account.

Description

inn is distributed on a variety of Linux platforms. The program is written under the assumption that the directory in which it stores temporary files is a private directory. On some platforms, it may be configured to create temporary files in /tmp or /var/tmp, both of which are world-writeable directories. This may leave inn subject to modification of files either by symbolic links, or by direct modification of the temporary files.

Impact

By creating a symbolic link named for the temporary file and pointed toward an inn configuration file, an attacker may cause modification of these files (or any other file writable by the news user). Should the attacker manage to control the content of these files, it may be possible to gain access to the news account.

Solution

Apply vendor patches; see the Systems Affected section below.

Reconfigure inn to use a non-world-writable temporary directory.

Vendor Information

964488
 

CVSS Metrics

Group Score Vector
Base
Temporal
Environmental

References

Acknowledgements

This vulnerability was first described by Greg Kroah-Hartman.

This document was last modified by Tim Shimeall.

Other Information

CVE IDs: CVE-2001-0139
Severity Metric: 5.40
Date Public: 2001-01-10
Date First Published: 2001-09-27
Date Last Updated: 2001-09-27 14:12 UTC
Document Revision: 14

Sponsored by CISA.