CVE-2026-121287
Security Advisory 0221
An unauthenticated attacker on an adjacent network segment can send crafted RIPv2 packets to a RIP-enabled interface on the device to trigger the Rip agent crash without providing valid credentials. Repeated exploitation reliably interrupts routing service on the affected device, which may also disrupt routing for other devices that depend on it. In a worst-case scenario, the vulnerability may allow an attacker to execute arbitrary code on the affected device.
Fixes and workarounds
Workaround
switch(config)# router rip switch(config-router-rip)# shutdown switch(config-router-rip)# end Note: disabling RIP or changing network statements may withdraw routes and interrupt connectivity. Plan a change window, confirm alternate routing, and verify the resulting configuration and route behavior.
Source: CNA: AristaAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| EOS Arista Networks Platforms: 710 Series, 720D Series, 720XP/722XPM Series, 750X Series, 7010TX Series, 7020R/R4 Series, 7130 Series running EOS, 7170 Series, 7050X3/X4 Series, 7060X/X2/X4/X5/X6/XE7 Series, 7260X/X3 Series, 7280R/R2/R3/R4 Series, 7300X/X3 Series, 7320X Series, 7358X4 Series, 7368X4 Series, 7388X5 Series, 7500R/R2/R3 Series, 7800R3/R4 Series, 7700R4 Series, AWE 5000 Series, AWE 7200R Series, CloudEOS, cEOS-lab, vEOS-lab, CloudVision eXchange, virtual or physical appliance |
4.37.0F (affected, custom) ≥ 4.36.0F; ≤ 4.36.2F (affected, custom) ≥ 4.35.0F; ≤ 4.35.6M (affected, custom) ≥ 4.34.0F; ≤ 4.34.8M (affected, custom) ≥ 4.33.0F; ≤ 4.33.10M (affected, custom) ≥ 4.32.0F; < 4.33.0F (affected, custom) ≥ 1.0.0; < 4.32.0F (affected, custom) Other versions: unaffected |
CNA: Arista |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 3.1 / 8.8 high |
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CNA: Arista |
| 4.0 / 7.7 high |
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:L/SA:N | CNA: Arista |
| 4.0 / 7.7 high |
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:L/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 | NVD: [email protected] |
| 3.1 / 8.8 high |
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | NVD: [email protected] |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
For agents and automation
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