vulntracker.iovulntracker.io
© 2026 vulntracker.io

CVE-2026-22321

Stack-Based Buffer Overflow in CLI Login Username Handling over CLI

MEDIUM
5.3
CVSS Score
Published: March 18, 2026 at 07:34 AM UTC
Updated: June 17, 2026 at 10:19 AM UTC
77 products affected across 1 vendorFl Switch 2308 Pn FirmwareFl Switch 2314-2sfp Pn FirmwareFl Switch 2206-2fx Firmware

Using FL SWITCH 2005 by Phoenix Contact?

Get instant alerts when new vulnerabilities affect FL SWITCH 2005 - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Start FreeSign In
Severity
MEDIUM5.3
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Fl Nat 2008 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Nat 2208 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Nat 2304-2gc 2SFP Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2005 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2008 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2008F Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2016 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2105 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2108 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement
Fl Switch 2116 Firmware· Phoenix Contact
60%
0.0.0 ≤ v < 3.530.0.0
Affected range stops below 3.53, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

Source: cverecord
https://certvde.com/de/advisories/VDE-2025-104

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMCERTVDE
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-121

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Create accountSign in
Free plan, no card