CVE-2026-73435 Security Advisory 0171
An unauthenticated attacker on the same broadcast segment can cause OSPFv2 adjacency flapping and packet loss, disrupting routing across the domain.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-73435?
CVE-2026-73435 is a high-severity denial of service vulnerability in Arista Networks EOS, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
On affected platforms running Arista EOS with Open Shortest Path First version 2 (OSPFv2) configured, a specially crafted OSPFv2 packet from an unauthenticated attacker on the same broadcast segment, with OSPFv2 authentication configured can cause adjacency flapping and packet loss. The disruption can affect routing across the broader OSPF domain.
Weakness: CWE-345
Which versions are affected by CVE-2026-73435?
How do I fix CVE-2026-73435?
No fix has been published for CVE-2026-73435 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-73435 being exploited?
There is no known exploitation of CVE-2026-73435 in the wild and no public exploit code.
Sources
Also known as GHSA-x3fc-rhxr-g7jr.