CVE-2026-22321 Stack-Based Buffer Overflow in CLI Login Username Handling over CLI
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.
Problem types: cwe_id: CWE-121
description: CWE-121 Stack-based Buffer Overflow
Affected products: vendor: Phoenix Contact
product: FL SWITCH 2005
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2008
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2016
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2105
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2108
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2116
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2204-2TC-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2205
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206-2FX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206-2FX SM
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206-2FX SM ST
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206-2FX ST
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206-2SFX PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2206C-2FX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2207-FX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2207-FX SM
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2208
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2208 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2208C
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2212-2TC-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2214-2FX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2214-2FX SM
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2214-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2214-2SFX PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2216
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2216 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2304-2GC-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2306-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2306-2SFP PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2308
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2308 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2312-2GC-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2314-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2314-2SFP PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2316
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2316 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2404-2TC-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2406-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2406-2SFX PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2408
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2408 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2412-2TC-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2414-2SFX
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2414-2SFX PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2416
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2416 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2504-2GC-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2506-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2506-2SFP PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2508
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2508 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2512-2GC-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2514-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2514-2SFP PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2516
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2516 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2608
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2608 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2708
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2708 PN
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2303-8SP1
default_status: unaffected
vendor: Phoenix Contact
product: FL NAT 2008
default_status: unaffected
vendor: Phoenix Contact
product: FL NAT 2208
default_status: unaffected
vendor: Phoenix Contact
product: FL NAT 2304-2GC-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2008F
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2316/K1
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2506-2SFP/K1
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 2508/K1
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH TSN 2316
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH TSN 2312-2GC-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH TSN 2314-2SFP
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 5924-4GC
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 5916-8GC-4SFP+
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 5924SFP-4GC
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 5924-4SFP+
default_status: unaffected
vendor: Phoenix Contact
product: FL SWITCH 5916SFP-8GC-4SFP+
default_status: unaffected
CVSS v3.1: attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 5.3
baseSeverity: MEDIUM
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
version: 3.1
Credits: lang: en
value: Gabriele Quagliarella from Nozomi Networks
Published: 2026-03-18T07:34:36.289Z