CVE-2021-28511 (GCVE-0-2021-28511)
Vulnerability from cvelistv5 – Published: 2022-08-05 16:47 – Updated: 2026-06-02 14:07
VLAI
EPSS
VEX
Title
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 t ...
Summary
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.
Severity
5.8 (Medium)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-26 20:14 UTC
CWE
- CWE-284 - Improper Access Control
Assigner
Arista
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://www.arista.com/en/support/advisories-noti… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| Arista Networks | EOS |
Affected:
4.24.0 , ≤ 4.24.9
(custom)
Affected: 4.25.0 , ≤ 4.25.8 (custom) Affected: 4.26.0 , ≤ 4.26.5 (custom) Affected: 4.27.0 , ≤ 4.27.3 (custom) |
Date Public
2022-07-19 00:00
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