CVE-2021-21002 json
Denial of Service in Phoenix Contact FL COMSERVER UNI products
published 2021-06-25 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8411
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 61%
- public exploits
- 0
- none known
Summary
In Phoenix Contact FL COMSERVER UNI in versions < 2.40 a invalid Modbus exception response can lead to a temporary denial of service.
Patch / fix
- Phoenix Contact FL COMSERVER 2.40
Exploit prediction
0.96% 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 | 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 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
Affected products
- Phoenix Contact FL COMSERVER
Classification
- Weakness
-
- CWE-772 Missing Release of Resource after Effective Lifetime
References
-
cert.vde.com
/en-us/advisories/vde-2021-022
third-party-advisory
Sources
- CVE List CVE-2021-21002
- NVD CVE-2021-21002
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