TI-2026-15961 Aliases CVE-2026-19655 GHSA-986v-7qw9-p5p6

Improper input validation in Arista EOS

LOW 31CWE-20Published 2026-09-15 · Updated 2026-09-16

Key facts

Attack vector: Adjacent network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: —
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

On affected platforms running Arista EOS with Dynamic Host Configuration Protocol (DHCP) relay/snooping configured with the information option (Option 82), or with the DHCP server configured with match criteria based on the information option, an unauthenticated attacker connected to a client-facing VLAN(s) where the relay is configured can send a specially crafted packet that causes the DHCP Relay service to restart.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00303 23rd percentileScored 2026-11-08

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Arista	EOS	4.35.0 – 4.35.5M; 4.34.0 – 4.34.7.1M; 4.33.0 – 4.33.9M	—	No fix listed	CNA

EOS VendorArista Affected 4.35.0 – 4.35.5M; 4.34.0 – 4.34.7.1M; 4.33.0 – 4.33.9M Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-19655
2026-10-03 Alias added: GHSA-986v-7qw9-p5p6

References

Advisory 1

https://www.arista.com/en/support/advisories-notices/security-advisory/24711-security-advisory-0155

TI-2026-79524 Privilege escalation in Arista VeloCloud Orchestrator on-premises KEVCVSS 4.0CRITICAL 9.4
TI-2026-63212 Improper input validation in Arista VeloCloud Orchestrator On-Prem KEVCVSS 4.0CRITICAL 9.5
TI-2026-13992 VeloCloud Orchestrator OS Command Injection KEVCVSS 4.0CRITICAL 10.0
TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
TI-2026-23989 crypto: algif_aead - Revert to operating out-of-place KEVCVSS 3.1HIGH 7.8

See all 216 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences