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.
References1
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 21 · as of 8 November 2026
- CWE
- CWE-125
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