CVE-2021-1591 : A vulnerability in the EtherChannel port subscription logic of Cisco Nexus 9500 Series Switches could allow an unauthent

A vulnerability in the EtherChannel port subscription logic of Cisco Nexus 9500 Series Switches could allow an unauthenticated, remote attacker to bypass access control list (ACL) rules that are configured on an affected device. This vulnerability is due to oversubscription of resources that occurs when applying ACLs to port channel interfaces. An attacker could exploit this vulnerability by attempting to access network resources that are protected by the ACL. A successful exploit could allow the attacker to access network resources that would be protected by the ACL that was applied on the port channel interface.

Published 2021-08-25 20:15:12

Updated 2022-07-08 18:25:15

Source Cisco Systems, Inc.

View at NVD, CVE.org

Vulnerability category: BypassGain privilege

Exploit prediction scoring system (EPSS) score for CVE-2021-1591

EPSS FAQ

0.12%

Probability of exploitation activity in the next 30 days EPSS Score History

~ 46 %

Percentile, the proportion of vulnerabilities that are scored at or less

CVSS scores for CVE-2021-1591

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source
5.0	MEDIUM	AV:N/AC:L/Au:N/C:N/I:P/A:N	10.0	2.9	NIST
Access Vector: Network Access Complexity: Low Authentication: None Confidentiality Impact: None Integrity Impact: Partial Availability Impact: None
5.8	MEDIUM	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N	3.9	1.4	Cisco Systems, Inc.
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None Scope: Changed Confidentiality: None Integrity: Low Availability: None
5.3	MEDIUM	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N	3.9	1.4	NIST
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None Scope: Unchanged Confidentiality: None Integrity: Low Availability: None

Products affected by CVE-2021-1591

Cisco » Nx-os » Version: 9.3(4)
cpe:2.3:o:cisco:nx-os:9.3\(4\):*:*:*:*:*:*:*
Matching versions
When used together with: Cisco » Nexus 9500 16-slot » Version: N/A
When used together with: Cisco » Nexus 9500 4-slot » Version: N/A
When used together with: Cisco » Nexus 9500 8-slot » Version: N/A
When used together with: Cisco » Nexus 9504 » Version: N/A
When used together with: Cisco » Nexus 9508 » Version: N/A
When used together with: Cisco » Nexus 9516 » Version: N/A

Vulnerability Details : CVE-2021-1591

Exploit prediction scoring system (EPSS) score for CVE-2021-1591

CVSS scores for CVE-2021-1591

CWE ids for CVE-2021-1591

References for CVE-2021-1591

Products affected by CVE-2021-1591