CVE Intelligence
Medium Memory corruption

CVE-2026-22320 — Stack-Based Buffer Overflow in TFTP File-Transfer Command Handling over CLI

A stack-based buffer overflow in the CLI's TFTP file‑transfer command handling allows a low-privileged attacker with Telnet/SSH access to trigger memory corruption by supplying unexpected or oversized filename input. Exploitation results in the corruption of the internal buffer, causing the CLI and web dashboard to become unavailable and leading to a denial of service.

Published Mar 18, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: CERTVDE

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.3% (30-day exploitation probability)+3
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.32%
ahead of 23% of scored CVEs · Oct 14, 2026
Affects
Phoenix Contact
FL NAT 2008 and 76 more
CVSS base
6.5
Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Phoenix Contact FL NAT 2008, Phoenix Contact FL NAT 2208, Phoenix Contact FL NAT 2304-2GC-2SFP…).
  2. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  3. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Phoenix Contact FL NAT 2008 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL NAT 2208 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL NAT 2304-2GC-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2005 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2008 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2008F ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2016 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2105 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2108 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2116 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2204-2TC-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2205 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206-2FX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206-2FX SM ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206-2FX SM ST ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206-2FX ST ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206-2SFX PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2206C-2FX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2207-FX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2207-FX SM ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2208 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2208 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2208C ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2212-2TC-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2214-2FX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2214-2FX SM ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2214-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2214-2SFX PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2216 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2216 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact Fl Switch 2303-8sp1 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2304-2GC-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2306-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2306-2SFP PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2308 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2308 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2312-2GC-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2314-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2314-2SFP PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2316 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2316 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2316/K1 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2404-2TC-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2406-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2406-2SFX PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2408 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2408 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2412-2TC-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2414-2SFX ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2414-2SFX PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2416 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2416 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2504-2GC-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2506-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2506-2SFP PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2506-2SFP/K1 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2508 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2508 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2508/K1 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2512-2GC-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2514-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2514-2SFP PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2516 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2516 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2608 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2608 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2708 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 2708 PN ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 5916-8GC-4SFP+ ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 5916SFP-8GC-4SFP+ ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 5924-4GC ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 5924-4SFP+ ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH 5924SFP-4GC ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH TSN 2312-2GC-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH TSN 2314-2SFP ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP
Phoenix Contact FL SWITCH TSN 2316 ≥ 0.0.0 and < 3.53 Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
6.5 CVSS 3.1 Medium 2.8 3.6 info@cert.vde.com via NIST National Vulnerability Database
6.5 CVSS 3.1 Medium — — CERTVDE via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: info@cert.vde.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-121 · Stack-based Buffer Overflow

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.32%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · phoenix contact/fl switch 2005, phoenix contact/fl switch 2008, phoenix contact/fl switch 2016, phoenix contact/fl switc
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 6.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Awaiting Analysis
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Mar 18, 2026 · CERTVDE

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

Elsewhere on this site

Phoenix Contact
every CVE for this vendor
Memory corruption
same class
CWE-121
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-22323 Cross‑Site Request Forgery in Link Aggregation Configuration Mar 18, 2026
  • CVE-2026-22322 Stored Cross‑Site Scripting in Link Aggregation Name Handling Mar 18, 2026
  • CVE-2026-22321 Stack-Based Buffer Overflow in CLI Login Username Handling over CLI Mar 18, 2026
  • CVE-2026-22318 Stack-Based Buffer Overflow in File Transfer Parameter Handling Mar 18, 2026
  • CVE-2026-22319 Stack-Based Buffer Overflow in File Install Parameter Handling Mar 18, 2026
  • CVE-2026-22317 Command Injection Vulnerability in Root CA Certificate Transfer Workflow Mar 18, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-22320 is "Stack-Based Buffer Overflow in TFTP File-Transfer Command Handling over CLI", rated Medium. It affects FL NAT 2008 (Phoenix Contact); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.5 describes technical severity. EPSS 0.32% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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