Schneider Electric IGSS

1. EXECUTIVE SUMMARY

• CVSS v3 7.8
• ATTENTION: Low attack complexity
• Vendor: Schneider Electric
• Equipment: IGSS (Interactive Graphical SCADA System)
• Vulnerabilities: Out-of-bounds Write, Out-of-bounds Read, Access of Uninitialized Pointer, Use After Free, Release of Invalid Pointer or Reference, Improper Limitation of a Pathname to a Restricted Directory

2. RISK EVALUATION

Successful exploitation of these vulnerabilities may result in remote code execution, which could result in an attacker gaining access to the Windows Operating System on the machine used to import CGF and WSP files.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following versions of Interactive Graphical SCADA System (IGSS) are affected:

• IGSS Definition (Def.exe) v15.0.0.21140 and prior

3.2 VULNERABILITY OVERVIEW

3.2.1    OUT-OF-BOUNDS WRITE CWE-787

Exploitation of this vulnerability could result in loss of data or remote code execution due to missing length checks when a malicious CGF file is imported to IGSS Definition.

CVE-2021-22750 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.2    OUT-OF-BOUNDS WRITE CWE-787

Exploitation of this vulnerability could result in disclosure of information or execution of arbitrary code due to lack of input validation when a malicious CGF (Configuration Group File) is imported to IGSS Definition.

CVE-2021-22751 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.3    OUT-OF-BOUNDS WRITE CWE-787

Exploitation of this vulnerability could result in loss of data or remote code execution due to missing size checks when a malicious WSP (Workspace) file is being parsed by IGSS Definition.

CVE-2021-22752 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.4    OUT-OF-BOUNDS READ CWE-125

Exploitation of this vulnerability could result in loss of data or remote code execution due to missing length checks when a malicious WSP file is being parsed by IGSS Definition.

CVE-2021-22753 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.5    OUT-OF-BOUNDS WRITE CWE-787

Exploitation of this vulnerability could result in loss of data or remote code execution due to lack of proper validation of user-supplied data when a malicious CGF file is imported to IGSS Definition.

CVE-2021-22754 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.6    OUT-OF-BOUNDS WRITE CWE-787

Exploitation of this vulnerability could result in disclosure of information or remote code execution due to lack of sanity checks on user-supplied data when a malicious CGF file is imported to IGSS Definition.

CVE-2021-22755 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.7    OUT-OF-BOUNDS READ CWE-125

Exploitation of this vulnerability could result in disclosure of information or remote code execution due to lack of user-supplied data validation when a malicious CGF file is imported to IGSS Definition.

CVE-2021-22756 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.8    OUT-OF-BOUNDS READ CWE-125

Exploitation of this vulnerability could result in disclosure of information or remote code execution due to lack of validation on user-supplied input data when a malicious CGF file is imported to IGSS Definition.

CVE-2021-22757 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.9    ACCESS OF UNINITIALIZED POINTER CWE-824

Exploitation of this vulnerability could result in loss of data or remote code execution due to lack of validation of user-supplied input data when a malicious CGF file is imported to IGSS Definition. 

CVE-2021-22758 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.10    USE AFTER FREE CWE-416

Exploitation of this vulnerability could result in loss of data or remote code execution due to use of unchecked input data when a malicious CGF file is imported to IGSS Definition. 

CVE-2021-22759 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.11    RELEASE OF INVALID POINTER OR REFERENCE CWE-763

Exploitation of this vulnerability could result in loss of data or remote code execution due to missing checks of user-supplied input data when a malicious CGF file is imported to IGSS Definition.

CVE-2021-22760 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.12    IMPROPER RESTRICTION OF OPERATIONS WITHIN THE BOUNDS OF A MEMORY BUFFER CWE-119

Exploitation of this vulnerability could result in disclosure of information or remote code execution due to missing length check on user supplied data when a malicious CGF file is imported to IGSS Definition. 

CVE-2021-22761 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H).

3.2.13    IMPROPER LIMITATION OF A PATHNAME TO A RESTRICTED DIRECTORY CWE-22

Exploitation of this vulnerability could result in remote code execution when a malicious CGF or WSP file is being parsed by IGSS Definition. 

CVE-2021-22762 has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been assigned; 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: Commercial Facilities, Critical Manufacturing, Energy
• COUNTRIES/AREAS DEPLOYED: Worldwide
• COMPANY HEADQUARTERS LOCATION: France

3.4 RESEARCHER

Kimiya, working with Trend Micro’s Zero Day Initiative, and Michael Heinzl separately reported these vulnerabilities to CISA.

4. MITIGATIONS

Schneider Electric recommends users update to Version 15.0.0.21141 of the IGSS Definition module: Def.exe includes fixes for these vulnerabilities and is available for download through IGSS Master > Update IGSS Software, or at the link above.



If users choose not to apply the remediation provided above, they should immediately apply the following mitigations to reduce the risk of exploitation:

• Avoid importing CGF and WSP files from untrusted sources.

Please see Schneider Electric’s publication SEVD-2021-159-01 for more information.

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.

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

• Do not click web links or open unsolicited attachments in 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 exploits specifically target these vulnerabilities. These vulnerabilities are not exploitable remotely.