A vulnerability in the access control list (ACL) programming of Cisco IOS Software running on Cisco Industrial Ethernet 4000, 4010, and 500…

published 2024-09-25 2 y ago modified 2026-06-17 4 mo ago also EUVD-2024-18180

cvss: 5.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 36%
public exploits: 0; none known

A vulnerability in the access control list (ACL) programming of Cisco IOS Software running on Cisco Industrial Ethernet 4000, 4010, and 5000 Series Switches could allow an unauthenticated, remote attacker to bypass a configured ACL. This vulnerability is due to the incorrect handling of IPv4 ACLs on switched virtual interfaces when an administrator enables and disables Resilient Ethernet Protocol (REP). An attacker could exploit this vulnerability by attempting to send traffic through an affected device. A successful exploit could allow the attacker to bypass an ACL on the affected device.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 2 y ago (2024-09-25)

Exploit prediction

0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD	3.1	5.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N

Affected products

Cisco IOS

Classification

Weakness

CWE-284 Improper Access Control

Technology feeds

Cisco IOS rss critical rss

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-repacl-9eXgnBpD
vendor-advisory

Sources

CVE List CVE-2024-20465
NVD CVE-2024-20465

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Summary