CVE-2021-33541 json
Phoenix Contact: ILC1x Industrial controllers affected by Denial-of-Service vulnerability
published 2021-06-25 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-20233
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 74%
- public exploits
- 0
- none known
Summary
Phoenix Contact Classic Line Controllers ILC1x0 and ILC1x1 in all versions/variants are affected by a Denial-of-Service vulnerability. The communication protocols and device access do not feature authentication measures. Remote attackers can use specially crafted IP packets to cause a denial of service on the PLC's network communication module. A successful attack stops all network communication. To restore the network connectivity the device needs to be restarted. The automation task is not affected.
Exploit prediction
1.49% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C |
Affected products
- Phoenix Contact ILC1x
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
cert.vde.com
/en-us/advisories/vde-2021-019
third-party-advisory
Sources
- CVE List CVE-2021-33541
- NVD CVE-2021-33541
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