1. EXECUTIVE SUMMARY
- CVSS v3 6.3
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: EFACEC
- Equipment: UC 500
- Vulnerabilities: Cleartext Transmission of Sensitive Information, Open Redirect, Exposure of Sensitive Information to an Unauthorized Actor, Improper Access Control
2. RISK EVALUATION
Successful exploitation of these vulnerabilities could allow an attacker to retrieve sensitive information, gain unauthorized access to the product, or redirect users to malicious websites.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following version of EFACEC UC 500E, a HMI, is affected:
- UC 500E: version 10.1.0
3.2 Vulnerability Overview
3.2.1 CLEARTEXT TRANSMISSION OF SENSITIVE INFORMATION CWE-319
An attacker with network access could perform a man-in-the-middle (MitM) attack and capture sensitive information to gain unauthorized access to the application.
CVE-2023-50703 has been assigned to this vulnerability. A CVSS v3 base score of 6.3 has been calculated; the CVSS vector string is (AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N).
3.2.2 URL REDIRECTION TO UNTRUSTED SITE (‘OPEN REDIRECT’) CWE-601
An attacker could construct a URL within the application that causes a redirection to an arbitrary external domain and could be leveraged to facilitate phishing attacks against application users.
CVE-2023-50704 has been assigned to this vulnerability. A CVSS v3 base score of 4.3 has been calculated; the CVSS vector string is (AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).
3.2.3 EXPOSURE OF SENSITIVE INFORMATION TO AN UNAUTHORIZED ACTOR CWE-200
An attacker could create malicious requests to obtain sensitive information about the web server.
CVE-2023-50705 has been assigned to this vulnerability. A CVSS v3 base score of 5.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N).
3.2.4 IMPROPER ACCESS CONTROL CWE-284
A user without administrator permissions with access to the UC500 windows system could perform a memory dump of the running processes and extract clear credentials or valid session tokens.
CVE-2023-50706 has been assigned to this vulnerability. A CVSS v3 base score of 4.1 has been calculated; the CVSS vector string is (AV:P/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L).
3.3 BACKGROUND
- CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing, Energy
- COUNTRIES/AREAS DEPLOYED: Multiple
- COMPANY HEADQUARTERS LOCATION: Portugal
3.4 RESEARCHER
Aarón Flecha Menéndez of S21sec reported this vulnerability to CISA.
4. MITIGATIONS
EFACEC has released UC 500E version 10.1.1 to mitigate this vulnerability.
For more information, contact EFACEC support.
CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities, such as:
- Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
- Locate control system networks and remote devices behind firewalls and isolating them from business networks.
- When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices.
CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.
CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.
CISA also recommends users take the following measures to protect themselves from social engineering attacks:
- Do not click web links or open attachments in unsolicited email messages.
- Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams.
- Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.
No known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time.
5. UPDATE HISTORY
- December 19, 2023: Initial Publication
