Honeywell created an update that mitigates authentication bypass and cross-site scripting vulnerabilities in its FALCON XLWeb controllers, according to a report on ICS-CERT.
Martin Jartelius of Outpost24 has identified an authentication bypass vulnerability and Juan Francisco Bolivar found the cross-site scripting vulnerabilities. Jartelius tested the update to validate that it resolves the vulnerability he reported. These vulnerabilities are remotely exploitable.
The following Honeywell FALCON XLWeb controller versions suffer from the issues:
• FALCON Linux 2.04.01 or older
• FALCON XLWebExe 2.02.11 or older.
An attacker may use these vulnerabilities to generate a valid login for an administrative user on the Honeywell FALCON XLWeb controller giving the attacker full administrator access to the system.
Honeywell is a U.S.-based company that maintains offices worldwide.
FALCON XLWeb controllers are web-based SCADA systems. These controllers see action across several sectors including critical manufacturing, energy, water and wastewater systems, and others. According to Honeywell, the affected controllers see use mainly in Europe and the Middle East.
It is possible to gain access to the change password page without a valid session or authentication. This page could end up disclosing a user’s password hash or login as a user without knowing the user’s password, making it possible for an attacker to login as an administrative user.
CVE-2014-2717 is the case number assigned to this vulnerability, which has a CVSS v2 base score of 7.6.
The web server is vulnerable to several cross-site scripting attacks. By sending invalid input through the XL Web controllers, an attacker can execute arbitrary HTML and script code in another user’s browser session.
CVE-2014-3110 is the case number assigned to this vulnerability, which has a CVSS v2 base score of 4.3.
While no known public exploits specifically target these vulnerabilities, an attacker with a moderate skill would be able to exploit these vulnerabilities.
Honeywell posted a Security Bulletin on Centraline Partnerweb (login required) that tells how to update FALCON controllers to the latest version.
Honeywell also offers the following advice:
• FALCON controllers (referred to as “XLWeb”) can be found unprotected in the Internet. Because this poses the risk of unauthorized access, immediate action should be taken in order to protect them from unauthorized access.
• All Internet facing FALCON controllers should be operated either in internal networks, or use a coded VPN connection for internet access, in order to limit unauthorized access.