1. EXECUTIVE SUMMARY

CVSS v3 9.8
ATTENTION: Exploitable remotely/low attack complexity
Vendor: Rockwell Automation
Equipment: ThinManager ThinServer
Vulnerabilities: Improper Input Validation

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow an attacker to remotely delete arbitrary files with system privileges.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

Rockwell Automation reports this vulnerability affects the following versions of ThinManager ThinServer, a thin client and remote desktop protocol (RDP) server management software:

ThinManager ThinServer: Versions 11.0.0-11.0.6
ThinManager ThinServer: Versions 11.1.0-11.1.6
ThinManager ThinServer: Versions 11.2.0-11.2.6
ThinManager ThinServer: Versions 12.1.0-12.1.6
ThinManager ThinServer: Versions 12.0.0-12.0.5
ThinManager ThinServer: Versions 13.0.0-13.0.2
ThinManager ThinServer: Version 13.1.0

3.2 VULNERABILITY OVERVIEW

3.2.1 IMPROPER INPUT VALIDATION CWE-20

Due to improper input validation, an integer overflow condition exists in the affected products. When the ThinManager processes incoming messages, a read access violation occurs and terminates the process. A malicious user could exploit this vulnerability by sending a crafted synchronization protocol message.

CVE-2023-2914 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

3.2.2 IMPROPER INPUT VALIDATION CWE-20

Due to improper input validation, a path traversal vulnerability exists when the ThinManager processes a certain function. If exploited, an unauthenticated remote threat actor can delete arbitrary files with system privileges. A malicious user could exploit this vulnerability by sending a specifically crafted synchronization protocol message.

CVE-2023-2915 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

3.2.3 IMPROPER INPUT VALIDATION CWE-20

Due to improper input validation, a path traversal vulnerability exists, via the file name field, when the ThinManager processes a certain function. If exploited, an unauthenticated remote attacker can upload arbitrary files to any directory on the disk drive where ThinServer.exe is installed. A malicious user could exploit this vulnerability by sending a crafted synchronization protocol message.

CVE-2023-2917 has been assigned to this vulnerability. A CVSS v3 base score of 9.8 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

3.3 BACKGROUND

CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing
COUNTRIES/AREAS DEPLOYED: Worldwide
COMPANY HEADQUARTERS LOCATION: United States

3.4 RESEARCHER

Rockwell Automation reported these vulnerabilities to CISA.

4. MITIGATIONS

Rockwell Automation recommends customers apply the following mitigations:

ThinManager ThinServer: Versions 11.0.0-11.2.6: Update to 11.0.7
ThinManager ThinServer: Versions 11.1.0-11.1.6: Update to 11.1.7
ThinManager ThinServer: Versions 11.2.0-11.2.6: Update to 11.2.8
ThinManager ThinServer: Versions 12.1.0-12.1.6: Update to 12.1.7
ThinManager ThinServer: Versions 12.0.0-12.0.5: Update to 12.0.6
ThinManager ThinServer: Versions 13.0.0-13.0.2: Update to 13.0.3
ThinManager ThinServer: Version 13.1.0: Update to 13.1.1

Customers using the affected software are encouraged to apply mitigations, if possible. Additionally, Rockwell Automation encourages customers to implement suggested security best practices to minimize the risk of vulnerability.

Update to the corrected software versions.
Limit remote access for TCP Port 2031 to known thin clients and ThinManager servers.
Security Best Practices

For more information, see Rockwell Automation’s Security Advisory.

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 at 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.

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.

No known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time.