CVE-2021-41292Public exploitNetwork attack vector

Unauthenticated HVAC control via trusted UCLS cookie

Published Sep 30, 2021 · Updated Sep 17, 2024

Authentication bypass in ECOA BAS controllers allows remote attackers to control HVAC systems through a crafted authentication cookie. The web interface accepts a UCLS cookie value of 19 or greater as authenticated, allowing access to protected menu.jsp resources without validating a session. Network access to the controller's web service is sufficient to disclose sensitive data and alter building or smart-home physical controls.

CVSS severity9.8
Critical
EPSS probability1.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in ECOA BAS controllers allows remote attackers to control HVAC systems through a crafted authentication cookie. The web interface accepts a UCLS cookie value of 19 or greater as authenticated, allowing access to protected menu.jsp resources without validating a session. Network access to the controller's web service is sufficient to disclose sensitive data and alter building or smart-home physical controls.

The record

CVE
CVE-2021-41292
Published
Sep 30, 2021
Updated
Sep 17, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-288, T0819
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8TWCERT/CCCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-288Authentication Bypass Using an Alternate Path or Channel
T0819Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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