Vulnerability in Phoenix Contact Fl Nat

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. The device needs to be rebooted afterwards.

Vulnerability class: Race Condition

EPSS: 0.007 (48.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-21005?
CVE-2021-21005 is a high-severity vulnerability in Phoenix Contact Fl Nat, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.5/10. Published 2021-06-25.
How severe is CVE-2021-21005?
High severity. CVSS v3 base score is 7.5 out of 10.