Apache .htaccess File Integer Overflow Lets Local Users Execute Arbitrary Code
SecurityTracker Alert ID: 1026267|
SecurityTracker URL: http://securitytracker.com/id/1026267
(Links to External Site)
Updated: Feb 1 2012|
Original Entry Date: Nov 2 2011
Execution of arbitrary code via local system, User access via local system|
Fix Available: Yes Vendor Confirmed: Yes Exploit Included: Yes |
Version(s): prior to 2.2.22|
A vulnerability was reported in Apache. A local user can obtain elevated privileges on the target system.|
A local user can create a specially crafted .htaccess file to trigger an integer overflow in ap_pregsub() and execute arbitrary code on the target system with the privileges of the target web service.
A demonstration exploit is available at:
The original advisory is available at:
halfdog reported this vulnerability.
A local user can obtain elevated privileges on the target system.|
The vendor has issued a fix (2.2.22).|
The vendor's advisory is available at:
Vendor URL: httpd.apache.org/ (Links to External Site)
|Underlying OS: Linux (Any), UNIX (Any), Windows (Any)|
This archive entry has one or more follow-up message(s) listed below.|
Source Message Contents
Date: Wed, 02 Nov 2011 11:55:26 +0000|
Subject: [Full-disclosure] Integer Overflow in Apache ap_pregsub via mod-setenvif
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An exploitable integer overflow in apache allows to crash the apache
process or execution of arbitrary code as user running apache. To
exploit the vulnerability, a crafted .htaccess file has to be placed
on the server, therefore the vulnerability impact is rated "Low".
See advisory for more information about the vulnerability and (very
bad) example to execute arbitrary code, using racy code.
It should be possible to execute code without the need for a race
using crafted stop sequences, but I haven't managed to do it so far.
Perhaps someone else might take up the challenge.
PGP: 156A AE98 B91F 0114 FE88 2BD8 C459 9386 feed a bee
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