CVE-2026-73468

Adjacent multicast disruption via premature state expiry

Published Sep 16, 2026 · Updated Sep 16, 2026

Control-flow error in PIM on affected Arista EOS releases allows adjacent attackers to interrupt multicast traffic with a crafted packet. PIM Sparse Mode processing accepts the packet and prematurely expires multicast forwarding state on the receiving interface. Exposure requires IPv4 or IPv6 PIM Sparse Mode on the targeted interface, and the resulting blackhole temporarily stops downstream multicast delivery.

CVSS severity6.5
Medium
EPSS probability0.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Control-flow error in PIM on affected Arista EOS releases allows adjacent attackers to interrupt multicast traffic with a crafted packet. PIM Sparse Mode processing accepts the packet and prematurely expires multicast forwarding state on the receiving interface. Exposure requires IPv4 or IPv6 PIM Sparse Mode on the targeted interface, and the resulting blackhole temporarily stops downstream multicast delivery.

The record

CVE
CVE-2026-73468
Published
Sep 16, 2026
Updated
Sep 16, 2026
Vendor
Arista Networks
Product
Arista EOS
Classifications
CWE-670, T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.0 <4.33.0F
  2. Affected versionversion=4.33.0F <=4.33.8M
  3. Affected versionversion=4.34.0F <=4.34.7.1M
  4. Affected versionversion=4.35.0F <=4.35.5M
  5. Affected versionversion=4.36.0F <=4.36.1F

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Arista Networks · Arista EOSversion=1.0.0 <4.33.0F; version=4.33.0F <=4.33.8M; version=4.34.0F <=4.34.7.1M; version=4.35.0F <=4.35.5M; version=4.36.0F <=4.36.1F

Published CVSS scores

7.1Arista NetworksCVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L
6.5Arista NetworksCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-670Always-Incorrect Control Flow Implementation
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo