CVE-2021-40366Network attack vector

Credential disclosure and data modification via cleartext HTTP

Published Nov 9, 2021 · Updated Aug 4, 2024

Cleartext transport in Siemens Climatix POL909 AWM before 11.34 and AWB before 11.42 allows man-in-the-middle attackers to read or alter data. The device web server sends sessions without TLS, exposing administrator credentials and permitting in-transit modification. An attacker must occupy a network path and a user must interact with the web server; confidentiality and integrity are affected.

CVSS severity6.4
Medium
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cleartext transport in Siemens Climatix POL909 AWM before 11.34 and AWB before 11.42 allows man-in-the-middle attackers to read or alter data. The device web server sends sessions without TLS, exposing administrator credentials and permitting in-transit modification. An attacker must occupy a network path and a user must interact with the web server; confidentiality and integrity are affected.

The record

CVE
CVE-2021-40366
Published
Nov 9, 2021
Updated
Aug 4, 2024
Vendor
Siemens
Product
Climatix POL909.50/STD
Classifications
CWE-311, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=All versions < V11.34

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Siemens · Climatix POL909.50/STDversion=All versions < V11.34
Siemens · Climatix POL909.80/STDversion=All versions < V11.42

Published CVSS scores

6.4Siemens ProductCERTCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:L/A:L
7.4NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:N

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-311Missing Encryption of Sensitive Data
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

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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