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TI-2021-09280 Aliases CVE-2021-27953GHSA-xfww-6hgp-m5c5

A NULL pointer dereference vulnerability exists on the ecobee3 lite 4.5.81.200 device in…

Priority LOW 36CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-476.

Summary

A NULL pointer dereference vulnerability exists on the ecobee3 lite 4.5.81.200 device in the HomeKit Wireless Access Control setup process. A threat actor can exploit this vulnerability to cause a denial of service, forcing the device to reboot via a crafted HTTP request.

Why it matters now

EPSS 0.01674 76th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:ecobee:ecobee3_lite_firmware:4.5.81.200:*:*:*:*:*:*:*4.5.81.200VulnerableEcobee
cpe:2.3:h:ecobee:ecobee3_lite:-:*:*:*:*:*:*:*not specified by NVDRunning onEcobee
  • cpe:2.3:o:ecobee:ecobee3_lite_firmware:4.5.81.200:*:*:*:*:*:*:* Versions 4.5.81.200 Vulnerable ·Ecobee
  • cpe:2.3:h:ecobee:ecobee3_lite:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Ecobee

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-27953
  2. 2026-10-03 Alias added: GHSA-xfww-6hgp-m5c5

References

  • TI-2021-09279 Hardcoded default root credentials exist on the ecobee3 lite 4.5.81.200 device. CVSS 3.1CRITICAL 9.8
  • TI-2021-09281 A heap-based buffer overflow vulnerability exists on the ecobee3 lite 4.5.81.200 device… CVSS 3.1HIGH 8.2

Sources