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Threats / Arista / CVE-2026-7473
CVE-2026-7473 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Arista Extensible Operating System vulnerability

Arista Extensible Operating System (EOS) contains an incomplete comparison with missing factors vulnerability when the switch incorrectly decapsulate and forwards other unexpected tunneled packet with a destination IP matching its configure

Verdict

Today item — known-exploited.

Confirmed exploited in the wild (CISA KEV). Prioritize remediation now and verify exposure.

CISA KEV Yes · 2026-06-095EPSS 0.01108 (verify live)6CVSS 6.93CISA SSVC Exploitation: active · Automatable: yes · Impact: total4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
4 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-06-09).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.01108 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 6.9 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N) · Affected: Arista, Extensible Operating System. Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 4.0, set at disclosure.
CVE.org ↗Reported
Weakness (CWE)
Mapped to CWE-1023 CWE-1023.CWE — CNA-assigned (CVE.org); the weakness class drives how the flaw is exploited.
CVE.org ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
CISA-ADP ↗Reported
Currency of the record
CISA added this to its KEV catalog 4 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board

Attacker/business narrative framing is pending triage for this record — see Coverage & confidence below. Facts and verdict above are derived deterministically from the public feed.

04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • 4 reported-exploitation source(s)
  • CVSS 6.9 — CNA-assigned (CVE.org)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping — CNA-assigned (CVE.org)
  • Catalogued by Arista (CNA)
  • Named finder/reporter credit (CVE.org)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • Attacker/business narrative framing pending triage.
  • Disclosure & credit2
    Catalogued by AristaCNA
    Credited with finding itScott Christiansen, Lukas Peitz, Rich Compton, and Jonathan Davis at Comcastfinder