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Apache vulnerable to buffer overflow when expanding environment variables

Vulnerability Note VU#481998

Original Release Date: 2004-09-17 | Last Revised: 2004-09-17


There is a buffer overflow vulnerability in ap_resolve_env() function of Apache that could allow a local user to gain elevated privileges.


The Apache HTTP Server is a freely available web server that runs on a variety of operating systems including Unix, Linux, and Microsoft Windows. The ap_resolve_env() function is responsible for expanding environment variables when parsing configurations files such as .htaccess or httpd.conf. There is a vulnerability in this function that could allow a local user to trigger a buffer overflow.

The Apache Software Foundation notes that in order to exploit this vulnerability, a local user would need to install the malicious configuration file on the server and force the server to parse this file.


A local user with the ability to force a vulnerable to server to parse a malicious configuration file could gain elevated privileges.


Upgrade or Apply Patch
Upgrade or apply patch as specified by your vendor. This issue is resolved in Apache version 2.0.51.

Vendor Information


Apache Affected

Updated:  September 17, 2004



Vendor Statement

We have not received a statement from the vendor.

Vendor Information

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


Please refer to the Apache Security Announcement.

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

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This vulnerability was reported by the Swedish IT Incident Centre within the National Post and Telecom Agency (SITIC).

This document was written by Damon Morda.

Other Information

CVE IDs: CVE-2004-0747
Severity Metric: 3.38
Date Public: 2004-09-15
Date First Published: 2004-09-17
Date Last Updated: 2004-09-17 20:09 UTC
Document Revision: 11

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