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Fencer Intel
medium 5.3

CVE-2026-22321 json

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

published 7mo ago modified 4mo ago also EUVD-2026-12790

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits
0
none known

Summary

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.

Patch / fix

  • Phoenix Contact FL SWITCH 2005 3.53
  • Phoenix Contact FL SWITCH 2008 3.53
  • Phoenix Contact FL SWITCH 2016 3.53
  • Phoenix Contact FL SWITCH 2105 3.53
  • Phoenix Contact FL SWITCH 2108 3.53
  • Phoenix Contact FL SWITCH 2116 3.53
  • Phoenix Contact FL SWITCH 2204-2TC-2SFX 3.53
  • Phoenix Contact FL SWITCH 2205 3.53
  • Phoenix Contact FL SWITCH 2206-2FX 3.53
  • Phoenix Contact FL SWITCH 2206-2FX SM 3.53
  • Phoenix Contact FL SWITCH 2206-2FX SM ST 3.53
  • Phoenix Contact FL SWITCH 2206-2FX ST 3.53
  • Phoenix Contact FL SWITCH 2206-2SFX 3.53
  • Phoenix Contact FL SWITCH 2206-2SFX PN 3.53
  • Phoenix Contact FL SWITCH 2206C-2FX 3.53
  • Phoenix Contact FL SWITCH 2207-FX 3.53
  • Phoenix Contact FL SWITCH 2207-FX SM 3.53
  • Phoenix Contact FL SWITCH 2208 3.53
  • Phoenix Contact FL SWITCH 2208 PN 3.53
  • Phoenix Contact FL SWITCH 2208C 3.53
  • Phoenix Contact FL SWITCH 2212-2TC-2SFX 3.53
  • Phoenix Contact FL SWITCH 2214-2FX 3.53
  • Phoenix Contact FL SWITCH 2214-2FX SM 3.53
  • Phoenix Contact FL SWITCH 2214-2SFX 3.53
  • Phoenix Contact FL SWITCH 2214-2SFX PN 3.53
  • Phoenix Contact FL SWITCH 2216 3.53
  • Phoenix Contact FL SWITCH 2216 PN 3.53
  • Phoenix Contact FL SWITCH 2304-2GC-2SFP 3.53
  • Phoenix Contact FL SWITCH 2306-2SFP 3.53
  • Phoenix Contact FL SWITCH 2306-2SFP PN 3.53

Is CVE-2026-22321 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
7mo ago

Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

  • Phoenix Contact FL SWITCH 2005
  • Phoenix Contact FL SWITCH 2008
  • Phoenix Contact FL SWITCH 2016
  • Phoenix Contact FL SWITCH 2105
  • Phoenix Contact FL SWITCH 2108
  • Phoenix Contact FL SWITCH 2116
  • Phoenix Contact FL SWITCH 2204-2TC-2SFX
  • Phoenix Contact FL SWITCH 2205
  • Phoenix Contact FL SWITCH 2206-2FX
  • Phoenix Contact FL SWITCH 2206-2FX SM
  • Phoenix Contact FL SWITCH 2206-2FX SM ST
  • Phoenix Contact FL SWITCH 2206-2FX ST
  • Phoenix Contact FL SWITCH 2206-2SFX
  • Phoenix Contact FL SWITCH 2206-2SFX PN
  • Phoenix Contact FL SWITCH 2206C-2FX
  • Phoenix Contact FL SWITCH 2207-FX
  • Phoenix Contact FL SWITCH 2207-FX SM
  • Phoenix Contact FL SWITCH 2208
  • Phoenix Contact FL SWITCH 2208 PN
  • Phoenix Contact FL SWITCH 2208C
  • Phoenix Contact FL SWITCH 2212-2TC-2SFX
  • Phoenix Contact FL SWITCH 2214-2FX
  • Phoenix Contact FL SWITCH 2214-2FX SM
  • Phoenix Contact FL SWITCH 2214-2SFX
  • Phoenix Contact FL SWITCH 2214-2SFX PN
  • Phoenix Contact FL SWITCH 2216
  • Phoenix Contact FL SWITCH 2216 PN
  • Phoenix Contact FL SWITCH 2304-2GC-2SFP
  • Phoenix Contact FL SWITCH 2306-2SFP
  • Phoenix Contact FL SWITCH 2306-2SFP PN
  • Phoenix Contact FL SWITCH 2308
  • Phoenix Contact FL SWITCH 2308 PN
  • Phoenix Contact FL SWITCH 2312-2GC-2SFP
  • Phoenix Contact FL SWITCH 2314-2SFP
  • Phoenix Contact FL SWITCH 2314-2SFP PN
  • Phoenix Contact FL SWITCH 2316
  • Phoenix Contact FL SWITCH 2316 PN
  • Phoenix Contact FL SWITCH 2404-2TC-2SFX
  • Phoenix Contact FL SWITCH 2406-2SFX
  • Phoenix Contact FL SWITCH 2406-2SFX PN
  • Phoenix Contact FL SWITCH 2408
  • Phoenix Contact FL SWITCH 2408 PN
  • Phoenix Contact FL SWITCH 2412-2TC-2SFX
  • Phoenix Contact FL SWITCH 2414-2SFX
  • Phoenix Contact FL SWITCH 2414-2SFX PN
  • Phoenix Contact FL SWITCH 2416
  • Phoenix Contact FL SWITCH 2416 PN
  • Phoenix Contact FL SWITCH 2504-2GC-2SFP
  • Phoenix Contact FL SWITCH 2506-2SFP
  • Phoenix Contact FL SWITCH 2506-2SFP PN

Classification

Weakness
  • CWE-121 Stack-based Buffer Overflow

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.