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 the session to close. Because other CLI sessions remain unaffected, the impact is limited to a low‑severity availability disruption.
Vulnerability class: Buffer Overflow
EPSS: 0.004 (29.3th 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
- Phoenix Contact Fl Nat 2008 — versions 0.0.0
- Phoenix Contact Fl Nat 2208 — versions 0.0.0
- Phoenix Contact Fl Nat 2304-2gc-2sfp — versions 0.0.0
- Phoenix Contact Fl Switch 2005 — versions 0.0.0
- Phoenix Contact Fl Switch 2008 — versions 0.0.0
- Phoenix Contact Fl Switch 2008f — versions 0.0.0
- Phoenix Contact Fl Switch 2016 — versions 0.0.0
- Phoenix Contact Fl Switch 2105 — versions 0.0.0
- Phoenix Contact Fl Switch 2108 — versions 0.0.0
- Phoenix Contact Fl Switch 2116 — versions 0.0.0
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.