7.0
HIGH CVSS 4.0
CVE-2026-73438
Security Advisory 0172
Description

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.

INFO

Published Date :

Sept. 16, 2026, 10:16 a.m.

Last Modified :

Sept. 16, 2026, 10:16 a.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-73438 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Arista_networks eos
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 HIGH c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7
CVSS 4.0 HIGH [email protected]
Solution
Update Arista EOS to patch the OSPFv3 agent crash vulnerability.
  • Update Arista EOS to the latest version.
  • Apply the vendor-supplied patch for OSPFv3.
  • Restart the OSPFv3 agent if necessary.
  • Verify OSPFv3 adjacency recovery.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-73438.

URL Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/24728-security-advisory-0172
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-73438 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-73438 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-73438 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-73438 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Sep. 16, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 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
    Added CVSS V3.1 AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-617
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/73xxx/CVE-2026-73438.json">CVE-2026-73438</a>
    Added Reference https://www.arista.com/en/support/advisories-notices/security-advisory/24728-security-advisory-0172
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.