ICS Advisory

AGG Software Web Server Plugin

Last Revised
Alert Code
ICSA-21-161-02

1. EXECUTIVE SUMMARY

  • CVSS v3 8.2
  • ATTENTION: Exploitable remotely/low attack complexity
  • Vendor: AGG Software
  • Equipment: Web Server
  • Vulnerabilities: Path Traversal, Cross-site Scripting

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow remote code execution and exposure of arbitrary system files.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Web Server may be bundled with any Data Logger:

  • v4.0.40.1014 and prior (webserver.dll)

3.2 VULNERABILITY OVERVIEW

3.2.1    PATH TRAVERSAL CWE-23

The affected product is vulnerable to a path traversal attack, which may allow an attacker to read arbitrary files from the file system.

CVE-2021-32964 has been assigned to this vulnerability. A CVSS v3 base score of 6.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N).

3.2.2    IMPROPER NEUTRALIZATION OF INPUT DURING WEB PAGE GENERATION ('CROSS-SITE SCRIPTING') CWE-79

The affected product is vulnerable to cross-site scripting, which may allow an attacker to remotely execute arbitrary code.

CVE-2021-32962 has been assigned to this vulnerability. A CVSS v3 base score of 8.2 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N).

3.3 BACKGROUND

  • CRITICAL INFRASTRUCTURE SECTORS: Multiple
  • COUNTRIES/AREAS DEPLOYED: Worldwide
  • COMPANY HEADQUARTERS LOCATION: Canada

3.4 RESEARCHER

Michael Heinzl reported these vulnerabilities to CISA.

4. MITIGATIONS

AGG recommends Web Server plugin users to update to 4.0.42 Build 512 or later. This plugin may be bundled with any of AGG data loggers.

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

  • Minimize network exposure for all control system devices and/or systems, and ensure that 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 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.

No known public exploits specifically target these vulnerabilities.

This product is provided subject to this Notification and this Privacy & Use policy.

Vendor

AGG Software