CVE-2021-34578Network attack vector

Unauthenticated settings access via crafted WBM requests

Published Aug 31, 2021 · Updated Sep 16, 2024

Improper authentication in WAGO PLC Web-Based Management through FW07 allows remote attackers to read and write device settings. WBM processes specially constructed settings requests without authenticating the requester; CERT@VDE identifies a race condition but discloses no narrower code locus. Network access to WBM is required, after which settings can be disclosed or altered and device operation can be disrupted.

CVSS severity9.8
Critical
EPSS probability0.96%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in WAGO PLC Web-Based Management through FW07 allows remote attackers to read and write device settings. WBM processes specially constructed settings requests without authenticating the requester; CERT@VDE identifies a race condition but discloses no narrower code locus. Network access to WBM is required, after which settings can be disclosed or altered and device operation can be disrupted.

The record

CVE
CVE-2021-34578
Published
Aug 31, 2021
Updated
Sep 16, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-287, T0836
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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

8.1NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8CERT@VDECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T0836Modify Parameter

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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