CVE-2026-73462: CWE-125 Out-of-bounds Read in Arista Networks EOS
On affected platforms running Arista EOS with IGMP (Internet Group Management Protocol) snooping configured (enabled by default on all VLANs), a network-adjacent unauthenticated attacker can send malformed network packets on an affected VLAN to cause the IGMP snooping agent to terminate unexpectedly. This results in a temporary disruption of multicast traffic management, which may cause multicast traffic to be flooded to all ports of the affected VLAN until the service recovers. Repeated exploitation could result in a prolonged loss of intended multicast forwarding behavior.
AI Analysis
Technical Summary
This vulnerability (CWE-125) exists in Arista EOS versions 4.33.0 through before 4.33.9M, 4.34.0 through before 4.34.8M, 4.35.0 through before 4.35.6M, and 4.36.0 through before 4.36.2F. When IGMP snooping is enabled (default on all VLANs), an attacker with network adjacency but no authentication can send malformed IGMP packets to trigger an out-of-bounds read, causing the IGMP snooping agent to terminate unexpectedly. This results in temporary loss of multicast traffic management, causing multicast traffic to flood all VLAN ports until the service restarts. The vulnerability impacts availability but does not affect confidentiality or integrity.
Potential Impact
The primary impact is a temporary denial of service affecting multicast traffic management on the affected VLAN. Multicast traffic is flooded to all ports, potentially causing network disruption. There is no impact on confidentiality or integrity. Repeated exploitation could extend the duration of multicast forwarding disruption.
Mitigation Recommendations
No vendor advisory or patch links are provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider disabling IGMP snooping on affected VLANs if feasible or monitoring for unusual multicast traffic flooding as a temporary mitigation.
CVE-2026-73462: CWE-125 Out-of-bounds Read in Arista Networks EOS
Description
On affected platforms running Arista EOS with IGMP (Internet Group Management Protocol) snooping configured (enabled by default on all VLANs), a network-adjacent unauthenticated attacker can send malformed network packets on an affected VLAN to cause the IGMP snooping agent to terminate unexpectedly. This results in a temporary disruption of multicast traffic management, which may cause multicast traffic to be flooded to all ports of the affected VLAN until the service recovers. Repeated exploitation could result in a prolonged loss of intended multicast forwarding behavior.
CVSS v3.1
Score 6.5medium
Affected software
Arista Networks
EOS
pkg:github/arista-networks/eosRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-125) exists in Arista EOS versions 4.33.0 through before 4.33.9M, 4.34.0 through before 4.34.8M, 4.35.0 through before 4.35.6M, and 4.36.0 through before 4.36.2F. When IGMP snooping is enabled (default on all VLANs), an attacker with network adjacency but no authentication can send malformed IGMP packets to trigger an out-of-bounds read, causing the IGMP snooping agent to terminate unexpectedly. This results in temporary loss of multicast traffic management, causing multicast traffic to flood all VLAN ports until the service restarts. The vulnerability impacts availability but does not affect confidentiality or integrity.
Potential Impact
The primary impact is a temporary denial of service affecting multicast traffic management on the affected VLAN. Multicast traffic is flooded to all ports, potentially causing network disruption. There is no impact on confidentiality or integrity. Repeated exploitation could extend the duration of multicast forwarding disruption.
Mitigation Recommendations
No vendor advisory or patch links are provided in the input data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, consider disabling IGMP snooping on affected VLANs if feasible or monitoring for unusual multicast traffic flooding as a temporary mitigation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Arista
- Date Reserved
- 2026-08-12T16:45:03.511Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aaaeb3055bf5e2cf50ccfaf
Added to database: 09/16/2026, 19:17:04 UTC
Last enriched: 09/16/2026, 19:31:38 UTC
Last updated: 09/17/2026, 03:43:33 UTC
Views: 10
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