CVE-2021-25909ZIV AUTOMATION 4CCT Denial of Service vulnerability
- 8.6HighCVSS base score
- 1.3%Exploitation in 30 daysEPSS · top 29% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
ZIV Automation 4CCT-EA6-334126BF firmware version 3.23.80.27.36371, allows an unauthenticated, remote attacker to cause a denial of service condition on the device. An attacker could exploit this vulnerability by sending specific packets to the port 7919.
Timeline
ID reserved
By INCIBE
- 7 days later
· 7 days later
Published
- 4 years later
· 4 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 |
|---|---|---|---|
| INCIBECNA (assigner) | 3.1 | High8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.3% · top 29% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.6.
Affected products
ZIV AUTOMATION · 4CCT-EA6-334126BF
- affected 3.23.80.27.36371
What to do
Solution: Update to firmware version 3.23.80.58.46120
References
References1
- https://www.incibe-cert.es/en/early-warning/ics-advisories/4cct-vulnerable-denial-service-attack (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-2021-12780 (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-2021-25909)Record last updated .