Race Condition Vulnerability in Phoenix Contact FL SWITCH SMCS series products

7.5 CVSS

Vulnerability Description

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. The device needs to be rebooted afterwards.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

This vulnerability has been discovered and reported by Anne Borcherding, Fraunhofer- Institut für Optronik, Systemtechnik und Bildauswertung IOSB. PHOENIX CONTACT thanks CERT@VDE for the coordination and support with this publication.

References

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

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Affected Vendor

Phoenix Contact

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Affected Software

FL SWITCH, FL NAT

Vulnerable Versions:

SMCS 16TX (2700996), SMCS 14TX/2FX (2700997), SMCS 14TX/2FX-SM (2701466), SMCS 8GT (2891123), SMCS 6GT/2SFP (2891479), SMCS 8TX-PN (2989103), SMCS 4TX-PN (2989093), SMCS 8TX (2989226), SMCS 6TX/2SFP (2989323), SMN 6TX/2POF-PN (2700290), SMN 8TX-PN (2989501), SMN 6TX/2FX (2989543), SMN 6TX/2FX SM (2989556), SMN 8TX (2989365), SMN 8TX-M (2702443)