CVE-2021-27662 - CVE House
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Status published High CVE-2021-27662

KT-1 Capture-replay

Vulnerability Description

The KT-1 door controller is susceptible to replay or man-in-the-middle attacks where an attacker can record and replay TCP packets. This issue affects Johnson Controls KT-1 all versions up to and including 3.01

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:

  • Dr. Dave Burke
  • Anthony Connor
  • Harrison Spisak

References

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Affected Vendor

Johnson Controls

View all reports →

Affected Software

KT-1
Vulnerable Versions:
all versions up to and including 3.01

Timeline

Official Publish: September 15th, 2021
Last Modified: September 17th, 2024
Added to House: July 21st, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-294

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.