Arista EOS up to 4.33.9M/4.34.7M/4.35.5M/4.36.1F VRRP improper authentication

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.4$0-$5k0.00

Summaryinfo

A vulnerability described as very critical has been identified in Arista EOS up to 4.33.9M/4.34.7M/4.35.5M/4.36.1F. The affected element is an unknown function of the component VRRP. The manipulation results in improper authentication. This vulnerability is known as CVE-2026-73444. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Arista EOS up to 4.33.9M/4.34.7M/4.35.5M/4.36.1F. Affected is an unknown code block of the component VRRP. The manipulation with an unknown input leads to a improper authentication vulnerability. CWE is classifying the issue as CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

On affected platforms running Arista EOS with VRRPv2 IP Authentication Header (IP-AH) authentication configured, an unauthenticated attacker with access to the layer 2 network segment on which VRRP is running could bypass VRRP authentication and claim the virtual router master role, enabling the attacker to intercept, modify, or discard traffic that hosts on the segment send to the virtual gateway address.

The advisory is available at arista.com. This vulnerability is traded as CVE-2026-73444 since 08/12/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 09/15/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.4

VulDB Base Score: 10.0
VulDB Temp Score: 10.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.7
CNA Vector (Arista): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/12/2026 CVE reserved
09/15/2026 +34 days Advisory disclosed
09/15/2026 +0 days VulDB entry created
09/15/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: arista.com
Status: Confirmed

CVE: CVE-2026-73444 (🔒)
GCVE (CVE): GCVE-0-2026-73444
GCVE (VulDB): GCVE-100-404850

Entryinfo

Created: 09/15/2026 23:42
Changes: 09/15/2026 23:42 (73)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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