CVE-2021-32978Network attack vector

Credential disclosure via programming protocol state reuse

Published Apr 4, 2022 · Updated Apr 16, 2025

Insufficiently protected credentials in AutomationDirect CLICK PLC C0-1x CPU firmware before 3.00 allow remote attackers to read a stored password. The programming protocol returns a previously entered password together with the controller lock state, preserving a successful credential for reuse. Network access to the programming service is sufficient, and the demonstrated consequence is credential disclosure and unauthorized PLC unlocking.

CVSS severity7.5
High
EPSS probability1.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficiently protected credentials in AutomationDirect CLICK PLC C0-1x CPU firmware before 3.00 allow remote attackers to read a stored password. The programming protocol returns a previously entered password together with the controller lock state, preserving a successful credential for reuse. Network access to the programming service is sufficient, and the demonstrated consequence is credential disclosure and unauthorized PLC unlocking.

The record

CVE
CVE-2021-32978
Published
Apr 4, 2022
Updated
Apr 16, 2025
Vendor
AutomationDirect
Product
CLICK PLC
Classifications
CWE-256, CWE-522, T1552
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 4, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 16, 2025Record 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=unspecified <3.00

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

AutomationDirect · CLICK PLCversion=unspecified <3.00

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5ICS-CERTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/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 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-256Plaintext Storage of a Password
CWE-522Insufficiently Protected Credentials
T1552Unsecured Credentials

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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