CVE-2026-77191: low-severity vulnerability in Arista Networks EOS
All of the CVEs covered in this advisory apply to affected platforms running Arista EOS with 802.1X authentication and authorization enabled and Access Control Lists (ACLs) configured for per-supplicant policy enforcement. An authenticated supplicant on an
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8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 2.1epss 0.2%
An authenticated supplicant on an adjacent network may bypass intended network authorization policy and send unrestricted traffic during a brief window (milliseconds to seconds) between the completion of the authentication phase and the full enforcement of its assigned ACL.
CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Affected products
Arista Networks · EOSRelated CVEs — Arista Networks EOS
In the same product, most dangerous first.
CVE-2026-7473MEDIUMArista EOS Unexpected Tunnel Protocol Decapsulation and Forwarding BypassEPSS 1.1%KEVCVE-2024-27890HIGHOn affected platforms running Arista EOS with OpenConfig configured, a gNMI Set request can be run when it should have been rejected (No SSL Profiles Enabled).EPSS 4.4%CVE-2021-28506CRITICALAn issue has recently been discovered in Arista EOS where certain gNOI APIs incorrectly skip authorization and authentication which could potentially allow a factory reset of the device.EPSS 1.4%CVE-2021-28510MEDIUMFor certain systems running EOS, a Precision Time Protocol (PTP) packet of a management/signaling message with an invalid Type-Length-Value (TLV) causes the PTP agent to restart. Repeated restarts of the service will make the service unavailable.EPSS 1.0%CVE-2021-28505HIGHOn affected Arista EOS platforms, if a VXLAN match rule exists in an IPv4 access-list that is applied to the ingress of an L2 or an L3 port/SVI, the VXLAN rule and subsequent ACL rules in that access list will ignore the specified IP protocol.EPSS 0.9%CVE-2023-24511MEDIUMOn affected platforms running Arista EOS with SNMP configured, a specially crafted packet can cause a memory leak in the snmpd process.EPSS 0.8%