CVE-2026-22321

CWE-121 — Stack-based Buffer Overflow3 documents3 sources
Severity
5.3MEDIUM
EPSS
0.0%
top 85.25%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
77
Phoenix Contact FL NAT 2008Phoenix Contact FL NAT 2208Phoenix Contact FL NAT 2304-2gc-2sfp+74 more
Timeline
PublishedMar 18

Description

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.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LExploitability: 3.9 | Impact: 1.4

Affected Packages77 packages

▶CVEListV5phoenix_contact/fl_nat_20080.0.0 — 3.53
▶CVEListV5phoenix_contact/fl_nat_22080.0.0 — 3.53
▶CVEListV5phoenix_contact/fl_switch_20050.0.0 — 3.53
▶CVEListV5phoenix_contact/fl_switch_20080.0.0 — 3.53
▶CVEListV5phoenix_contact/fl_switch_20160.0.0 — 3.53

🔴Vulnerability Details

2
CVEList
Stack-Based Buffer Overflow in CLI Login Username Handling over CLI↗2026-03-18
▶
GHSA
GHSA-j66g-mfcw-hrf3: A stack-based buffer overflow in the device's Telnet/SSH CLI login routine occurs when a unauthenticated attacker send an oversized or unexpected user↗2026-03-18
▶
CVE-2026-22321 (MEDIUM CVSS 5.3) | A stack-based buffer overflow in th | cvebase.io