9.6

CVE-2026-73437: arista networks eos

CVSS: 9.6v3.1CriticalAwaiting analysis
Published 15-09-2026Last modified 17-09-2026
Open JSON

Vulnerability summary

CVE-2026-73437 is a critical (CVSS 9.6) vulnerability in arista networks eos. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10.1% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.6/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.21%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 15-09-2026
    PublishedVulnerability first disclosed.
  2. 17-09-2026
    Last modifiedVulnerability information updated.

Description

On affected platforms running Arista EOS with Dynamic Host Configuration Protocol (DHCP) relay configured, an unauthenticated attacker with network access could send a crafted DHCP reply packet from an IP address that is not configured as a helper address, and the relay agent would forward it to clients without validating the source. This could allow the attacker to supply clients with malicious network configuration parameters, potentially resulting in traffic interception or denial of service for affected clients.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.21%

Chance of exploitation in the next 30 days

Percentile

10%

Versus all other CVEs

30-day change

+0.01 pp

From 0.20% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.21%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Arista networks1 product
  • eos≥ 4.36.0, ≤ 4.36.1F | ≥ 4.35.0, ≤ 4.35.5M | ≥ 4.34.0, ≤ 4.34.7.1M | ≥ 4.33.0, ≤ 4.33.9M

1 vendor · 1 product

References

1 links