CVSS 4.0
6.1 mediumCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:H/SC:N/SI:L/SA:LCVE-2026-121367 Security Advisory 0220
Medium (6.1) in arista networks eos. EPSS 0.3% estimated probability of exploitation activity in the next 30 days.
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.
Severity
CVSS 3.1
9.6 criticalCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:H- EPSS
- 0.3% estimated probability of exploitation activity in the next 30 days; 22nd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: yes · Technical impact: total, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-440 Expected Behavior Violation
- Published
- Modified
- Assigned by
- Arista (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- arista networks:eos
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Arista Networks EOS | from 1.0.0 before 4.33.0F |
| Arista Networks EOS | from 4.33.0F through 4.33.10M |
| Arista Networks EOS | from 4.34.0F through 4.34.8M |
| Arista Networks EOS | from 4.35.0F through 4.35.6M |
| Arista Networks EOS | from 4.36.0F through 4.36.2F |
| Arista Networks EOS | 4.37.0F |