# CVE-2026-120977: Security Advisory 0217

Status: published. Published: 2026-11-10. Updated: 2026-11-13.

On affected platforms running Arista EOS with 802.1X with Dynamic Host Configuration Protocol (DHCP) device profiling enabled, a network-adjacent attacker can send a crafted DHCP packet to force the device to record a spoofed device profile. This may potentially allow the authenticated supplicant to acquire unauthorized access to a network segment with elevated privileges.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Arista Networks / EOS: ≥ 4.31.2F; < 4.32.0F (affected, custom); ≥ 4.32.0F; < 4.33.0F (affected, custom); ≥ 4.33.0F; ≤ 4.33.9M (affected, custom); ≥ 4.34.0F; ≤ 4.34.7M (affected, custom); ≥ 4.35.0F; ≤ 4.35.5M (affected, custom); ≥ 4.36.0F; ≤ 4.36.2F (affected, custom). Source: CNA: Arista; platforms: 710 Series, 720D Series, 720XP/722XPM Series, 750X Series, 7010TX Series, 7020R/R4 Series, 7260X/X3 Series, 7280R/R2/R3/R4 Series, 7050X3/X4 Series, 7060X/X2/X4/X5/X6/XE7 Series, 7300X/X3 Series, 7320X Series, 7358X4 Series, 7368X4 Series, 7388X5 Series, 7500R/R2/R3 Series, 7700R4 Series, 7800R3/R4 Series

## Severity and prioritization

- CVSS 3.1: 8.2 (high); CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N; source: CNA: Arista

- CVSS 4.0: 7.1 (high); CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/SA:N; source: CNA: Arista

- CVSS 4.0: 7.1 (high); CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/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; source: NVD: psirt@arista.com

- CVSS 3.1: 8.2 (high); CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N; source: NVD: psirt@arista.com

- CISA KEV: No listing in collected sources

- EPSS: 0.16% as of 2026-11-12; percentile 5.30%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-807

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.arista.com/en/support/advisories-notices/security-advisory/25039-security-advisory-0217 (CNA: Arista; vendor-advisory)

- https://www.arista.com/en/support/advisories-notices/security-advisory/25039-security-advisory-0217 (psirt@arista.com)

## Provenance

- CNA: Arista: https://www.cve.org/CVERecord?id=CVE-2026-120977; retrieved 2026-11-13; source updated 2026-11-13

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-120977; retrieved 2026-11-13; source updated 2026-11-13

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-120977; retrieved 2026-11-13; source updated Not reported

Revision: fcaff84e5348a76946c4d20063d9da517a02e575d13ee154869f68daf96f3b7e

Canonical: https://y2.dev/cve/CVE-2026-120977

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