CVE-2021-32986Automation Direct CLICK PLC CPU Modules Authentication Bypass Using an Alternate Path or Channel
- 9.8CriticalCVSS base score
- 1.1%Exploitation in 30 daysEPSS · top 34% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
After Automation Direct CLICK PLC CPU Modules: C0-1x CPUs with firmware prior to v3.00 is unlocked by an authorized user, the unlocked state does not timeout. If the programming software is interrupted, the PLC remains unlocked. All subsequent programming connections are allowed without authorization. The PLC is only relocked by a power cycle, or when the programming software disconnects correctly.
Timeline
ID reserved
By icscert
- 11 months later
· 11 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| icscertCNA (assigner) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.1% · top 34% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
Automation Direct · CLICK PLC CPU Modules: C0-1x CPUs
- affected unspecified – < 3.00
What to do
Solution: Automation Direct reports these vulnerabilities are all mitigated by Version 3.00 and recommends users update software and firmware to the latest version. Automation Direct also recommends users follow its security guidelines.
References
References1
- https://www.cisa.gov/uscert/ics/advisories/icsa-21-166-02 (opens in a new tab)x_refsource_CONFIRMx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-19707 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-32986)Record last updated .