Arista EOS up to 4.34.7M/4.35.5M/4.36.1F Pimsm Agent input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k0.45

Summaryinfo

A vulnerability described as critical has been identified in Arista EOS up to 4.34.7M/4.35.5M/4.36.1F. This vulnerability affects unknown code of the component Pimsm Agent. The manipulation results in input validation. This vulnerability is identified as CVE-2026-77190. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in Arista EOS up to 4.34.7M/4.35.5M/4.36.1F. Affected is an unknown code block of the component Pimsm Agent. The manipulation with an unknown input leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on availability. CVE summarizes:

On affected platforms running Arista EOS, an unauthenticated attacker who is network-adjacent to the switch and able to connect to a device with PIM Sparse Mode and MLAG configured, can send malformed messages that cause the Pimsm agent to terminate unexpectedly. The Pimsm agent is automatically restarted, but repeated attacks can cause the agent to restart continuously, resulting in a sustained denial of service.

The advisory is available at arista.com. This vulnerability is traded as CVE-2026-77190 since 08/20/2026. 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 09/16/2026).

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

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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: 7.0
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.5
VulDB Temp Score: 7.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (Arista): 🔒

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
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

08/20/2026 CVE reserved
09/16/2026 +27 days Advisory disclosed
09/16/2026 +0 days VulDB entry created
09/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: arista.com
Status: Confirmed

CVE: CVE-2026-77190 (🔒)
GCVE (CVE): GCVE-0-2026-77190
GCVE (VulDB): GCVE-100-405606

Entryinfo

Created: 09/16/2026 12:19
Changes: 09/16/2026 12:19 (73)
Complete: 🔍
Cache ID: 216::103

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