Unauthenticated RCE in Arista EOS switches can give full control of network infrastructure used widely in enterprises and data centers.
CVE-2026-73456
Unauthenticated RCE in Arista EOS gNPSI allows full administrative takeover of switches.
Is CVE-2026-73456 being exploited?
Not confirmed. CVE-2026-73456 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 0.75% probability of exploitation in the next 30 days.
How severe is CVE-2026-73456?
CVE-2026-73456 is rated Critical with a CVSS score of 9.2. 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-2026-73456?
Yes. A fix has been recorded for CVE-2026-73456. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-73456 affect?
CVE-2026-73456 affects Arista EOS switches with gNPSI (Network Packet Sampling) enabled. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-73456?
Isolate/segment management plane, disable gNPSI, apply vendor updates from advisory when available
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated remote code execution via gNPSI request, granting full administrative control of affected switches and network disruption.
Immediate action required
- affected>= 4.36.0 and <= 4.36.1F
- affected>= 4.35.0 and <= 4.35.5M
- affected>= 4.34.2F and <= 4.34.7M
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.