CVE-2021-21003 json
Denial of Service Vulnerability in Phoenix Contact FL SWITCH SMCS series products
published 2021-06-25 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8412
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 61%
- public exploits
- 0
- none known
Summary
In Phoenix Contact FL SWITCH SMCS series products in multiple versions fragmented TCP-Packets may cause a Denial of Service of Web-, SNMP- and ICMP-Echo services. The switching functionality of the device is not affected.
Exploit prediction
0.95% chance of exploitation in the next 30 days, higher than 61% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Phoenix Contact FL SWITCH
- Phoenix Contact FL NAT
Classification
- Weakness
-
- CWE-404 Improper Resource Shutdown or Release
References
-
cert.vde.com
/en-us/advisories/vde-2021-023
third-party-advisory
Sources
- CVE List CVE-2021-21003
- NVD CVE-2021-21003
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