CVE-2026-121288

medium

Description

An unauthenticated attacker on an adjacent network segment can bypass MD5 authentication and have unauthorized RIP route updates accepted by the device. Successful exploitation requires that RIPv2 MD5 authentication is configured on the affected interface. An attacker who can inject crafted RIPv2 packets could cause the device to install routes that redirect network traffic through attacker-controlled paths, create routing loops, or blackhole traffic, disrupting network connectivity.

References

https://www.arista.com/en/support/advisories-notices/security-advisory/25043-security-advisory-0221

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-122809

Details

Source: Mitre, NVD

Published: 2026-11-10

Updated: 2026-11-13

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:A/AC:L/Au:N/C:N/I:C/A:C

Severity: High

CVSS v3

Base Score: 8.1

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Severity: High

CVSS v4

Base Score: 6.1

Vector: CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:L/SA:L

Severity: Medium

EPSS

EPSS: 0.00236