Skip to main content
EPSS 0.2%top 94%

CVE-2026-73435: CWE-345 Insufficient Verification of Data Authenticity in Arista Networks EOS

0
High
VulnerabilityCVE-2026-73435cvecve-2026-73435cwe-345
Published: 09/16/2026 (09/16/2026, 09:19:47 UTC)
Source: CVE Database V5
Vendor/Project: Arista Networks
Product: EOS

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.

CVSS v3.1

Score 8.2high

Attack Vector
Adjacent Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
Low
Availability
High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:H

Affected software

Arista Networks

EOS

Affected versions
>=4.36.0F <=4.36.1F>=4.35.0F <=4.35.5M>=4.34.0F <=4.34.7M>=4.33.0F <=4.33.9M>=1.0.0 <4.33.0F
GitHub Actionsmore threats →ai
arista-networks/eos
pkg:github/arista-networks/eos
Affected versions
>=1.0.0 <4.33.0F>=4.33.0F <=4.33.9M>=4.34.0F <=4.34.7M>=4.35.0F <=4.35.5M>=4.36.0F <=4.36.1F

Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/16/2026, 09:46:28 UTC

Technical Analysis

This vulnerability (CVE-2026-73435) involves insufficient verification of data authenticity (CWE-345) in Arista EOS when Open Shortest Path First version 2 (OSPFv2) is configured with authentication. An attacker on the same broadcast segment can send crafted OSPFv2 packets without authentication, leading to adjacency flapping and packet loss, which disrupts routing in the OSPF domain. The CVSS 3.1 score is 8.2 (high severity) with attack vector as adjacent network, low attack complexity, no privileges required, no user interaction, scope changed, no confidentiality impact, integrity impact low, and high availability impact.

Potential Impact

The vulnerability can cause routing instability by forcing OSPF adjacency flapping and packet loss, which can disrupt network routing across the OSPF domain. This impacts network availability but does not affect confidentiality and has limited integrity impact.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, network administrators should consider network segmentation or OSPF authentication configuration reviews to limit exposure from unauthenticated attackers on the same broadcast segment.

Pro Console: star threats, build custom feeds, automate alerts via Slack, email & webhooks.Upgrade to Pro

Technical Details

Data Version
5.2
Assigner Short Name
Arista
Date Reserved
2026-08-12T16:39:35.976Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 6aaa621555bf5e2cf54c8cd0

Added to database: 09/16/2026, 09:32:05 UTC

Last enriched: 09/16/2026, 09:46:28 UTC

Last updated: 09/16/2026, 22:11:11 UTC

Views: 11

Community Reviews

0 reviews

Crowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.

Sort by
Loading community insights…

Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.

Actions

PRO

Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.

Please log in to the Console to use AI analysis features.

Need more coverage?

Upgrade to Pro Console for AI refresh and higher limits.

For incident response and remediation, OffSeq services can help resolve threats faster.

Latest Threats

Breach by OffSeqOFFSEQFRIENDS — 25% OFF

Check if your credentials are on the dark web

Instant breach scanning across billions of leaked records. Free tier available.

Scan now
OffSeq TrainingCredly Certified

Lead Pen Test Professional

Technical5-day eLearningPECB Accredited
View courses