Advisoriesby IbisArista NetworksCVE-2026-73438
Arista Networks EOS: reachable assertion
No fix yet
On affected platforms running Arista EOS with Open Shortest Path First version 3 (OSPFv3) configured, an unauthenticated attacker on the same OSPFv3 broadcast domain can send a specially crafted set of packets that can cause the Ospf3 agent to restart unexpectedly. The crash results in the loss of all OSPFv3 adjacencies on the affected device and may disrupt routing across the broader OSPF domain until the agent recovers.
This issue was reported externally by Dravanet Inc., and Arista is not aware of any malicious exploitation of this vulnerability in customer networks.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| EOS Product | >= 4.36.0F, <= 4.36.1F | No fix yet |
| >= 4.35.0F, <= 4.35.5M | No fix yet | |
| >= 4.34.0F, <= 4.34.7M | No fix yet | |
| >= 4.33.0F, <= 4.33.9M | No fix yet |
Details and references
- CVSS 4.0
- CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/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-617