A security issue has been reported in mod_proxy. See
We have assigned CAN-2004-0492 to this issue.
The flaw affects Apache httpd 1.3.25 to 1.3.31 inclusive that have
mod_proxy enabled and configured. Apache httpd 2.0 is unaffected.
The security issue is a buffer overflow which can be triggered by
getting mod_proxy to connect to a remote server which returns an
invalid (negative) Content-Length. This results in a memcpy to the
heap with a large length value, which will in most cases cause the
Apache child to crash. This does not represent a significant Denial
of Service attack as requests will continue to be handled by other
Apache child processes.
In order to exploit this issue an attacker would need to get an
Apache installation that was configured as a proxy to connect to a
For Red Hat Enterprise Linux we do not believe that this issue can
lead to arbitrary code execution.
A patch to correct this issue is available. See:
Even though this is mitigated to being a minor issue we will produce
an update for Red Hat Enterprise Linux 2.1, including a fix for bug
#122637 and CAN-2004-0488.
RHSA-2004:245 in QA
An errata has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.