CVE-2021-40360Network attack vector

Account compromise via exposed password hash API

Published Feb 9, 2022 · Updated Aug 4, 2024

Information disclosure in Siemens SIMATIC WinCC and PCS 7 allows remote authenticated users to retrieve a local account password hash via an API. A public API on the remote server returns the hash of a local user account to an authenticated user instead of withholding credential material. Access to an affected-system account is required; the disclosed hash can be brute-forced and the recovered password used to log in to the server.

CVSS severity8.8
High
EPSS probability0.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Siemens SIMATIC WinCC and PCS 7 allows remote authenticated users to retrieve a local account password hash via an API. A public API on the remote server returns the hash of a local user account to an authenticated user instead of withholding credential material. Access to an affected-system account is required; the disclosed hash can be brute-forced and the recovered password used to log in to the server.

The record

CVE
CVE-2021-40360
Published
Feb 9, 2022
Updated
Aug 4, 2024
Vendor
Siemens
Product
SIMATIC WinCC
Classifications
CWE-522, CWE-200, T1110.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 9, 2022CVE 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 < V15 SP1 Update 7
  2. Affected versionversion=All versions < V16 Update 5
  3. Affected versionversion=All versions < V17 Update 2
  4. Affected versionversion=All versions < V7.4 SP1 Update 19
  5. Affected versionversion=All versions < V7.5 SP2 Update 6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Siemens · SIMATIC WinCCversion=All versions < V15 SP1 Update 7; version=All versions < V16 Update 5; version=All versions < V17 Update 2; version=All versions < V7.4 SP1 Update 19; version=All versions < V7.5 SP2 Update 6
Siemens · SIMATIC PCS 7version=All versions; version=All versions < V9.1 SP1

Published CVSS scores

8.8NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/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.

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

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-522Insufficiently Protected Credentials
CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1110.002Password Cracking

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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