Strix
75.6K

CVE-2026-121367

CRITICALCVSS 9.6/10EPSS 0.29%

Last modified

CVE-2026-121367 is a critical-severity vulnerability rated 9.6/10 on the CVSS scale. On affected Arista EOS platforms with Routing Information Protocol version 2 (RIPv2) configured, under certain conditions, RIPv2 might be silently enabled on management interfaces even when the RIP agent intends to disable it. It allows an unauthenticated attacker with access to the adjacent network to send crafted RIPv2 route advertisements to the device's management IP address. EPSS estimates a 0.29% chance of exploitation in the next 30 days.

Description

On affected Arista EOS platforms with Routing Information Protocol version 2 (RIPv2) configured, under certain conditions, RIPv2 might be silently enabled on management interfaces even when the RIP agent intends to disable it. It allows an unauthenticated attacker with access to the adjacent network to send crafted RIPv2 route advertisements to the device's management IP address. The device could accept and install those routes without authentication. Successful exploitation could allow the attacker to redirect traffic flows to an attacker-controlled destination, install more-specific routes that blackhole legitimate traffic, or otherwise disrupt network reachability for systems whose traffic passes through the affected device.

Metrics

CVSS 3.1
9.6/10

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

CVSS 4.0
6.1/10

CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:H/SC:N/SI:L/SA:L/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 Probability
0.29%

22.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
Arista NetworksEOS>= 1.0.0, < 4.33.0F; >= 4.33.0F, <= 4.33.10M; >= 4.34.0F, <= 4.34.8M; >= 4.35.0F, <= 4.35.6M; >= 4.36.0F, <= 4.36.2F; 4.37.0F

References

Timeline

Published
Last Modified
Status
Awaiting Analysis

Frequently Asked Questions

What is CVE-2026-121367?
On affected Arista EOS platforms with Routing Information Protocol version 2 (RIPv2) configured, under certain conditions, RIPv2 might be silently enabled on management interfaces even when the RIP agent intends to disable it. It allows an unauthenticated attacker with access to the adjacent network to send crafted RIPv2 route advertisements to the device's management IP address. The device could accept and install those routes without authentication. Successful exploitation could allow the attacker to redirect traffic flows to an attacker-controlled destination, install more-specific routes that blackhole legitimate traffic, or otherwise disrupt network reachability for systems whose traffic passes through the affected device.
How severe is CVE-2026-121367?
CVE-2026-121367 has a CVSS score of 9.6/10 (CRITICAL severity). The EPSS model estimates a 0.29% probability of exploitation in the next 30 days.
How do I fix CVE-2026-121367?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

View all 2026CVEs →

Are you affected by CVE-2026-121367?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST