Rewterz Threat Advisory – CVE-2021-27657 – ICS: Johnson Controls Metasys

Severity

High

Analysis Summary

CVE-2021-27657

Metasys servers, engines, and tools do not properly assign, modify, track, or check privileges for an actor, thus creating an unintended sphere of control for the said actor. Successful exploitation of this vulnerability could give an authenticated Metasys user an unintended level of access to the server file system, allowing them to access or modify system files by sending specifically crafted web messages to the Metasys system.

Impact

• Improper Privilege Management
• Privilege Escalation

Affected Vendors

Johnson Controls

Affected Products

• Metasys all versions

Remediation

Refer to vendor advisory for the complete list of affected products and their respective patches at https://us-cert.cisa.gov/ics/advisories/icsa-21-159-01