Arista EOS before 4.21.12M, 4.22.x before 4.22.7M, 4.23.x before 4.23.5M, and 4.24.x before 4.24.2F allows remote attackers to cause a deni…

published 2020-10-21 6y ago modified 2026-06-17 4mo ago also EUVD-2020-9309

cvss: 7.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.2%; EPSS 1.2% chance of exploitation in 30 days, percentile 68%
public exploits: 0; none known

Arista EOS before 4.21.12M, 4.22.x before 4.22.7M, 4.23.x before 4.23.5M, and 4.24.x before 4.24.2F allows remote attackers to cause a denial of service (restart of agents) by crafting a malformed DHCP packet which leads to an incorrect route being installed.

Patch / fix

fixed in 1

arista eos 4.21.12m, 4.22.7m, 4.23.5m, 4.24.2f

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Exploit prediction

1.21% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:N/A:P

References

arista.com /en/support/advisories-notices/security-advisories/11759-security-advisory-53
vendor-advisory

Sources

CVE List CVE-2020-17355
NVD CVE-2020-17355

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