CVE-2026-22321
MEDIUMCVSS 5.3/10EPSS 0.37%
Last modified
CVE-2026-22321 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. 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. EPSS estimates a 0.37% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Phoenix Contact | FL SWITCH 2005 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2008 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2016 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2105 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2108 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2116 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2204-2TC-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2205 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206-2FX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206-2FX SM | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206-2FX SM ST | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206-2FX ST | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206-2SFX PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2206C-2FX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2207-FX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2207-FX SM | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2208 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2208 PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2208C | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2212-2TC-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2214-2FX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2214-2FX SM | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2214-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2214-2SFX PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2216 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2216 PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2304-2GC-2SFP | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2306-2SFP | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2306-2SFP PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2308 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2308 PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2312-2GC-2SFP | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2314-2SFP | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2314-2SFP PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2316 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2316 PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2404-2TC-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2406-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2406-2SFX PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2408 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2408 PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2412-2TC-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2414-2SFX | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2414-2SFX PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2416 | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2416 PN | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2504-2GC-2SFP | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2506-2SFP | >= 0.0.0, < 3.53 |
| Phoenix Contact | FL SWITCH 2506-2SFP PN | >= 0.0.0, < 3.53 |
Showing 50 of 77 affected configurations. See the CNA advisory for the full list.
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
Frequently Asked Questions
What is 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.
How severe is CVE-2026-22321?
CVE-2026-22321 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.37% probability of exploitation in the next 30 days.
How do I fix CVE-2026-22321?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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