CVE-2026-73446
High
Description
On affected platforms running Arista EOS with IS-IS configured on a broadcast interface, an unauthenticated attacker can send a crafted IS-IS Hello Protocol Data Unit (PDU) that causes the device to tear down an established IS-IS adjacency. This may result in traffic disruption and loss of IP reachability for prefixes advertised through that adjacency.
SeverityHigh
CVSS7.4
Exploit probability—
ProductEOS
PublishedSep 16, 2026
First seenSep 16, 2026
Weakness typeCWE-696CWE-696
How to fix
Update
- Arista Networks EOS4.33.0F, 4.32.0F or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| Arista Networks EOS | 4.36.0 ≤ v ≤ 4.36.1F, 4.35.0 ≤ v ≤ 4.35.5M, 4.34.0 ≤ v ≤ 4.34.7.1M, 4.33.0 ≤ v ≤ 4.33.9M, 4.32.0 ≤ v < 4.33.0F, 4.31.0 ≤ v < 4.32.0F | 4.33.0F, 4.32.0F |
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