Arista NetworksCVE-2026-19655
Arista Networks EOS: improper input validation
High7.1CVE-2026-19655 · Published Sep 15, 2026 · updated Sep 16, 2026
On affected platforms running Arista EOS with Dynamic Host Configuration Protocol (DHCP) relay/snooping configured with the information option (Option 82), or with the DHCP server configured with match criteria based on the information option, an unauthenticated attacker connected to a client-facing VLAN(s) where the relay is configured can send a specially crafted packet that causes the DHCP Relay service to restart.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| EOS Product | >= 4.35.0, <= 4.35.5M | No fix yet |
| >= 4.34.0, <= 4.34.7.1M | No fix yet | |
| >= 4.33.0, <= 4.33.9M | No fix yet |
Details and references
- CVSS 4.0
- CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-20
More Arista Networks advisories
All Arista Networks| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 15 | Arista Networks EOS: denial of service | Medium6.5 | No fix yet |
| Sep 15 | On affected platforms running Arista EOS with VRRPv2 IP Authentication Header | Medium5.3 | No fix yet |
| Sep 15 | On affected platforms running Arista EOS with authenticated Bidirectional... | Critical9.2 | No fix yet |
| Sep 15 | Arista Networks EOS: secrets in logs | Medium6.0 | No fix yet |
| Sep 15 | Arista Networks EOS: secrets in logs | Medium6.0 | No fix yet |
| Sep 15 | Arista Networks EOS: secrets in logs | Medium6.0 | No fix yet |