1. EXECUTIVE SUMMARY

  • CVSS v3 7.8
  • ATTENTION: Low skill level to exploit
  • Vendor: Horner Automation
  • Equipment: Cscape
  • Vulnerability: Out-of-bounds Read

2. RISK EVALUATION

Successful exploitation of this vulnerability may allow code execution in the context of the current process.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Cscape, a control system application programming software, are affected:

  • Cscape: All versions prior to 9.90 SP3.5

3.2 VULNERABILITY OVERVIEW

3.2.1    OUT-OF-BOUNDS READ CWE-125

The affected application lacks proper validation of user-supplied data when parsing project files. This could lead to an out-of-bounds read. An attacker could leverage this vulnerability to execute code in the context of the current process.

CVE-2021-22663 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/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

Francis Provencher {PRL}, working with Trend Micro’s Zero Day Initiative, reported this vulnerability to CISA.

4. MITIGATIONS

Horner Automation recommends affected users update to the latest version of Cscape (Version 9.90 SP3.5). If outside of Americas, download here.
Users with questions regarding their specific Cscape installations should contact their local Horner Automation service support team at either:

CISA recommends users take the following measures to protect themselves from social engineering attacks:

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 us-cert.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 us-cert.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.

Source:

https://us-cert.cisa.gov/ics/advisories/icsa-21-035-02