CVE-2021-28511

published 2022-08-05

CVE-2021-28511: This advisory documents the impact of an internally found vulnerability in Arista EOS for security ACL bypass. The impact of this vulnerability is that the…

Priority P4 33 medium 6.5 CVSS 3.1

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

This advisory documents the impact of an internally found vulnerability in Arista EOS for security ACL bypass. The impact of this vulnerability is that the security ACL drop rule might be bypassed if a NAT ACL rule filter with permit action matches the packet flow. 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 as it should have been denied by the Security ACL. This can enable an ACL bypass.

Affected

8 ranges

Vendor	Product	Version range	Fixed in
arista	eos	<= 4.24.9	—
arista	eos	4.25.0 – 4.25.8	—
arista	eos	4.26.0 – 4.26.5	—
arista	eos	4.27.0 – 4.27.3	—
arista_networks	eos	4.24.0 – 4.24.9	—
arista_networks	eos	4.25.0 – 4.25.8	—
arista_networks	eos	4.26.0 – 4.26.5	—
arista_networks	eos	4.27.0 – 4.27.3	—

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CWE-284