CVE-2021-27657 - CVE House
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Status published High CVE-2021-27657

Metasys Improper Privilege Management

Vulnerability Description

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. This issue affects: Johnson Controls Metasys version 11.0 and prior versions.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Jakub Palaczynski

References

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Affected Vendor

Johnson Controls

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Affected Software

Metasys
Vulnerable Versions:
11.0

Timeline

Official Publish: June 4th, 2021
Last Modified: September 17th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses (CWE)

CWE-269

MITRE ATT&CK TTPs

T1078 Valid Accounts
Persistence
T1098 Account Manipulation
Privilege Escalation
T1548 Abuse Elevation Control Mechanism
Privilege Escalation
T1222 File and Directory Permissions Modification
Defense Evasion
T1134 Access Token Manipulation
Defense Evasion