CVE-2026-73446

HIGH
Published Sep 16, 2026 Modified Sep 16, 2026 CWE-696

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.

Is your site exposed to CVE-2026-73446?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.4
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0025
Probability of exploitation
0.16%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-696 CWE-696

References

Frequently Asked Questions

What is CVE-2026-73446? +
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. It has a CVSS v3.1 base score of 7.4 (HIGH).
How severe is CVE-2026-73446? +
CVE-2026-73446 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-73446? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-73446 — free, no signup required.