Cyber Resilience

CVE-2021-27663

High

Published: 30 August 2021

Published
30 August 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.2 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
EPSS Score 0.0073 73.1th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-27663 is a high-severity Improper Authorization (CWE-285) vulnerability in Johnsoncontrols Ac2000 Firmware. Its CVSS base score is 8.2 (High).

Operationally, ranked in the top 26.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

A vulnerability in versions 10.1 through 10.5 of Johnson Controls CEM Systems AC2000 allows a remote attacker to access to the system without adequate authorization. This issue affects: Johnson Controls CEM Systems AC2000 10.1; 10.2; 10.3; 10.4; 10.5.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

johnsoncontrols
ac2000 firmware
10.1 — 10.5

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-285

Documented procedures facilitate correct implementation and ongoing management of authorization decisions.

addresses: CWE-285

Periodic reviews identify and correct flaws in authorization decisions or enforcement.

addresses: CWE-285

The control's documentation requirement reduces improper authorization by ensuring only mission-justified actions bypass authentication.

addresses: CWE-285

Establishing permitted attributes and values, plus auditing changes, ensures authorization decisions are based on correctly managed policy data.

addresses: CWE-285

Explicitly mandates authorizing remote access types before permitting connections, directly mitigating improper authorization.

addresses: CWE-285

The control explicitly requires authorization of each wireless access type prior to permitting connections.

addresses: CWE-285

Mandating explicit authorization of mobile device connections reduces the risk of improper authorization decisions for system access.

addresses: CWE-285

Specifying access authorizations for each account and requiring approvals for account requests enforces proper authorization decisions.

References