How severe is CVE-2026-73458?

CVE-2026-73458 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2026-73458 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-73458?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2026-73458 published?

CVE-2026-73458 was published on 2026-09-15 and last updated on 2026-09-16.

CVE-2026-73458

CVE-2026-73458 is a high-severity vulnerability with a CVSS 3.x base score of 8.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-303.

Key facts

Severity: High (CVSS 3.x base score 8.2)
CVSS v4: 9.2
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-303
Published: 2026-09-15
Last modified: 2026-09-16

Description

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).

Frequently asked questions

What is CVE-2026-73458?: 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).
How severe is CVE-2026-73458?: CVE-2026-73458 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2026-73458 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-73458?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2026-73458 published?: CVE-2026-73458 was published on 2026-09-15 and last updated on 2026-09-16.

References

https://www.arista.com/en/support/advisories-notices/security-advisory/24710-security-advisory-0154

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