Unauthenticated remote root RCE in widely deployed Cisco Nexus 9000 switches (Silicon One); can disrupt data center and network infrastructure across organizations.
CVE-2026-20212
Unauthenticated remote root RCE in Cisco Nexus 9000 via TCP ports 43210/43211.
Is CVE-2026-20212 being exploited?
Not confirmed. CVE-2026-20212 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.53% probability of exploitation in the next 30 days.
How severe is CVE-2026-20212?
CVE-2026-20212 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-20212?
Yes. A fix has been recorded for CVE-2026-20212. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-20212 affect?
CVE-2026-20212 affects Cisco Nexus 9000 Series switches (Silicon One integration). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-20212?
Apply Cisco patch immediately; block TCP 43210/43211; restrict L3 VRF management access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated remote code execution as root; attacker can run arbitrary commands, crash S1HAL and reload the device.
Immediate action required
- affected10.3(1)
- affected10.3(2)
- affected10.3(3)
- affected10.4(1)
- affected10.3(99w)
- affected10.3(3w)
- affected10.3(99x)
- affected10.3(3o)
- affected10.3(4)
- affected10.3(3p)
- affected10.3(4a)
- affected10.4(2)
- affected10.3(3q)
- affected10.3(5)
- affected10.4(3)
- affected10.3(3x)
- affected10.3(4g)
- affected10.5(1)
- affected10.3(3r)
- affected10.3(6)
- affected10.4(4)
- affected10.3(4h)
- affected10.5(2)
- affected10.3(7)
- affected10.4(5)
- affected10.5(3)
- affected10.4(4g)
- affected10.5(4)
- affected10.6(1)
- affected10.5(3t)
- affected10.3(8)
- affected10.4(6)
- affected10.5(3s)
- affected10.5(3e)
- affected10.5(3o)
- affected10.6(1s)
- affected10.6(2)
- affected10.5(3p)
- affected10.3(9)
- affected10.6(2s)
- affected10.6(3)
- affected10.4(7)
- affected10.5(5)
- affected10.6(2n)
- affected10.6(3s)
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.