Buffer overflow in Phoenix Contact Fl Nat 2008

CVE-2026-22321

A stack-based buffer overflow in the device's Telnet/SSH CLI login routine occurs when a unauthenticated attacker send an oversized or unexpected username input. An overflow condition crashes the thread handling the login attempt, forcing…

Vulnerability class: Buffer Overflow

EPSS: 0.000 (5.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-22321?
CVE-2026-22321 is a medium-severity vulnerability in Phoenix Contact Fl Nat 2008, classified under Stack-based Buffer Overflow. CVSS score: 5.3/10. Published 2026-03-18.
How severe is CVE-2026-22321?
Medium severity. CVSS v3 base score is 5.3 out of 10.