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CVE-2021-21003

Denial of Service Vulnerability in Phoenix Contact FL SWITCH SMCS series products

MEDIUM
5.3
CVSS Score
Published: June 25, 2021 at 06:25 PM UTC
Updated: June 17, 2026 at 03:34 AM UTC
30 products affected across 1 vendorFl Nat Smn 8TX M FirmwareFl Nat Smn 8TX FirmwareFl Switch Smcs 8TX Pn Firmware

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Severity
MEDIUM5.3
Exploit prediction
EPSS 0.9%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Fl Nat Smn 8TX Firmware· Phoenix Contact
95%
v ≤ 4.63
phoenixcontact-fl-nat-smn-8tx (same device)
Fl Nat Smn 8TX M Firmware· Phoenix Contact
95%
v ≤ 4.63
phoenixcontact-fl-nat-smn-8tx-m (same device)
Fl Switch Smcs 14TX /2fx Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-14tx-2fx (same device)
Fl Switch Smcs 14TX /2fx Sm Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-14tx-2fx-sm (same device)
Fl Switch Smcs 16TX Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-16tx (same device)
Fl Switch Smcs 4TX Pn Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-4tx-pn (same device)
Fl Switch Smcs 6GT /2sfp Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-6gt-2sfp (same device)
Fl Switch Smcs 6TX /2sfp Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-6tx-2sfp (same device)
Fl Switch Smcs 8GT Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-8gt (same device)
Fl Switch Smcs 8TX Firmware· Phoenix Contact
95%
v ≤ 4.70
phoenixcontact-fl-switch-smcs-8tx (same device)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

x_refsource_CONFIRMThird Party Advisory
Source: [email protected]
https://cert.vde.com/en-us/advisories/vde-2021-023

CVSS

5.3MEDIUMCERTVDE
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-404

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