VulnerabilityModified

CVE-2021-21005

In Phoenix Contact FL SWITCH SMCS series products in multiple versions if an attacker sends a hand-crafted TCP-Packet with the Urgent-Flag set and the Urgent-Pointer set to 0, the network stack will crash.

HIGH 7.5EPSS 0.68%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.68%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

CVSS 3.1: 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.68% probability · 52th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-362
Affected: phoenixcontact/fl switch smcs 16tx firmware · phoenixcontact/fl switch smcs 14tx\/2fx firmware · phoenixcontact/fl switch smcs 14tx\/2fx-sm firmware · phoenixcontact/fl switch smcs 8gt firmware · phoenixcontact/fl switch smcs 6gt\/2sfp firmware · phoenixcontact/fl switch smcs 8tx-pn firmware · phoenixcontact/fl switch smcs 4tx-pn firmware · phoenixcontact/fl switch smcs 8tx firmware · phoenixcontact/fl switch smcs 6tx\/2sfp firmware · phoenixcontact/fl switch smn 6tx\/2pof-pn firmware · phoenixcontact/fl switch smn 8tx-pn firmware · phoenixcontact/fl switch smn 6tx\/2fx firmware · phoenixcontact/fl switch smn 6tx\/2fx sm firmware · phoenixcontact/fl nat smn 8tx firmware · phoenixcontact/fl nat smn 8tx-m firmware
Source: info@cert.vde.com

EPSS trend

EPSS 0.7% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

https://cert.vde.com/en-us/advisories/vde-2021-023Third Party Advisory
https://cert.vde.com/en-us/advisories/vde-2021-023Third Party Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.