[UNIX] apachetop Insecure Temporary File Creation

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apachetop Insecure Temporary File Creation
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SUMMARY

<http://clueful.shagged.org/apachetop/> apachetop - "Realtime Apache
monitoring tool. A curses-based top-like display for Apache information,
including requests per second, bytes per second, most popular URLs, etc."

apachetop creates a predictable temporary file, this allows a local
attacked to use the program to preform symlink attacks.

DETAILS

Vulnerable Systems:
* apachetop versions 0.12.5 and prior

The vulnerability is caused due to temporary file being created
insecurely. This can be exploited via symlink attacks in combination to
create and overwrite arbitrary files with the privileges of the user
running the affected script.

CVE Information:
<http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2005-2660>
CAN-2005-2660

Solution:
Apply : apachetop_CAN-2005-2660.patch
Patch from Steve Kemp (Debian)
<http://bugs.gentoo.org/attachment.cgi?id=69342>
http://bugs.gentoo.org/attachment.cgi?id=69342

Vulnerable code :
Take a look at : src/apachetop.h

247 #define DEBUG_OUTPUT "/tmp/atop.debug"

Then in : src/apachetop.cc

85 cf.debug = true;

1103 int dprintf(const char *fmt, ...) /* {{{ */
1104 {
1105 FILE *d;
1106 va_list args;
1107
1108 if (cf.debug && (d = fopen(DEBUG_OUTPUT, "a")))
1109 {
1110 va_start(args, fmt);
1111 vfprintf(d, fmt, args);
1112 fclose(d);
1113 va_end(args);
1114 }
1115
1116 return 0;
1117 } /* }}} */

ADDITIONAL INFORMATION

The information has been provided by <mailto:eromang@zataz.net> Eric
Romang.
The original article can be found at:
<http://www.zataz.net/adviso/apachetop-09022005.txt>
http://www.zataz.net/adviso/apachetop-09022005.txt
The bug report can be found at:
<http://bugs.gentoo.org/show_bug.cgi?id=104473>
http://bugs.gentoo.org/show_bug.cgi?id=104473

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