Paper/Archive/CVE-2026-73458

CVE-2026-73458

Arista Networks EOS — On affected platforms running Arista EOS with authenticated Bidirectional Forwarding Detection (BFD) sessions configured, a specially crafted packet can cause the BFD session(s) to go down. This may result in undesirable network changes because various rou

EPSS 0.4%CVSS 9.2

critical.is priorityof 100

CVSS 9.2 (CNA)9.2 / 10 × 3027.6 Not in CISA KEV+300.0 EPSS percentile 34.3.343 × 206.9 No public exploit+100.0 SSVC exploitation: none+100.0

Description · from the CVE record

On affected platforms running Arista EOS with authenticated Bidirectional Forwarding Detection (BFD) sessions configured, a specially crafted packet can cause the BFD session(s) to go down. This may result in undesirable network changes because various routing protocols monitor status on BFD session(s).

Affected

ProductAffectedFixed inSource

EOS4.36.0 – 4.36.1F–CNA

EOS4.35.0 – 4.35.5M–CNA

EOS4.34.0 – 4.34.7M–CNA

EOS4.33.0 – 4.33.8M–CNA

Scores by source

Arista (CNA)9.2CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:H

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

CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: partial

References

advisoryarista.com/en/support/advisories-notices/security-advisory/24710-security-advisory-0154