OFFIS DCMTK

1. EXECUTIVE SUMMARY

• CVSS v3 7.5 *ATTENTION: Exploitable from an adjacent network/low attack complexity
• Vendor: OFFIS
• Equipment: DCMTK
• Vulnerabilities: Path Traversal, Relative Path Traversal, NULL Pointer Dereference

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow an attacker to cause a denial-of-service condition, write malformed DICOM files into arbitrary directories, and gain remote code execution.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of DCMTK, libraries and software that process DICOM image files, are affected:

• DCMTK: All versions prior to 3.6.7

3.2 VULNERABILITY OVERVIEW

3.2.1 IMPROPER LIMITATION OF A PATHNAME TO A RESTRICTED DIRECTORY (‘PATH TRAVERSAL’) CWE-22

The affected product’s service class provider (SCP) is vulnerable to path traversal, allowing an attacker to write DICOM files into arbitrary directories under controlled names. This could allow remote code execution.

CVE-2022-2119 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).

3.2.2 RELATIVE PATH TRAVERSAL CWE-23

The affected product’s service class user (SCU) is vulnerable to relative path traversal, allowing an attacker to write DICOM files into arbitrary directories under controlled names. This could allow remote code execution.

CVE-2022-2120 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).

3.2.3 NULL POINTER DEREFERENCE CWE-476

The affected product has a NULL pointer dereference vulnerability while processing DICOM files, which may result in a denial-of-service condition.

CVE-2022-2121 has been assigned to this vulnerability. A CVSS v3 base score of 6.5 has been calculated; the CVSS vector string is (AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

3.3 BACKGROUND

• CRITICAL INFRASTRUCTURE SECTORS: Healthcare and Public Health
• COUNTRIES/AREAS DEPLOYED: Worldwide
• COMPANY HEADQUARTERS LOCATION: Germany

3.4 RESEARCHER

Noam Moshe of Claroty reported these vulnerabilities to CISA.

4. MITIGATIONS

OFFIS recommends all users update to Version 3.6.7 or later. For more information see Bug #1021

CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should:

• Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the Internet.
• Locate control system networks and remote devices behind firewalls and isolate them from the business network.
• When remote access is required, use 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 its 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. Several recommended 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 on cisa.gov in the Technical Information Paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.

Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to CISA for tracking and correlation against other incidents.

No known public exploits specifically target these vulnerabilities.