PT-2022-9903 · Arista · Arista Eos

Published 2022-07-19 · Updated 2022-08-15 · CVE-2021-28511

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Name of the Vulnerable Software and Affected Versions Arista EOS (affected versions not specified)

Description The issue affects the security ACL bypass in Arista EOS. It occurs when a NAT ACL rule filter with permit action matches the packet flow, potentially bypassing the security ACL drop rule. This could allow a host with an IP address in a range that matches the range allowed by a NAT ACL and a range denied by a Security ACL to be forwarded incorrectly. The result is an ACL bypass. This issue was discovered internally, and there is no known malicious use in customer networks.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Improper Access Control

Weakness Enumeration

CWE-284

Related Identifiers

CVE-2021-28511

Affected Products

Arista Eos

References · 3

• 🔥 https://arista.com/en/support/advisories-notices/security-advisory/15862-security-advisory-0078 · Exploit
• https://osv.dev/vulnerability/CVE-2021-28511 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-28511 · Security Note