CVE-2024-20263
highpriority · track · 29EPSS 0.004 · 39 %ileDEEURUUSEPSS · scored 2026-10-26
A vulnerability with the access control list (ACL) management within a stacked switch configuration of Cisco Business 250 Series Smart Switches and Business 350 Series Managed Switches could allow an unauthenticated, remote attacker to bypass protection offered by a configured ACL on an affected device. This vulnerability is due to incorrect processing of ACLs on a stacked configuration when either the primary or backup switches experience a full stack reload or power cycle. An attacker could exploit this vulnerability by sending crafted traffic through an affected device. A successful exploit could allow the attacker to bypass configured ACLs, causing traffic to be dropped or forwarded in an unexpected manner. The attacker does not have control over the conditions that result in the device being in the vulnerable state. Note: In the vulnerable state, the ACL would be correctly applied on the primary devices but could be incorrectly applied to the backup devices.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Small Business Smart and Managed Switchescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.3–7.2
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (184)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2024-0191Cisco Small Business Produkte: Schwachstelle ermöglicht Umgehen von SicherheitsvorkehrungenDeutsch2024-01-24csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Cisco Small Business Switches ausnutzen, um Sicherheitsvorkehrungen zu umgehen.
- cisco-sa-sb-bus-acl-bypass-5zn9hNJkCisco Small Business Series Switches Stacked Reload ACL Bypass Vulnerability2024-01-24csaf · cisco_csafUS
A vulnerability with the access control list (ACL) management within a stacked switch configuration of Cisco Business 250 Series Smart Switches and Business 350 Series Managed Switches could allow an unauthenticated, remote attacker to bypass protection offered by a configured ACL on an affected device. This vulnerability is due to incorrect processing of ACLs on a stacked configuration when either the primary or backup switches experience a full stack reload or power cycle. An attacker could exploit this vulnerability by sending crafted traffic through an affected device. A successful exploit could allow the attacker to bypass configured ACLs, causing traffic to be dropped or forwarded in an unexpected manner. The attacker does not have control over the conditions that result in the device being in the vulnerable state. Note: In the vulnerable state, the ACL would be correctly applied on the primary devices but could be incorrectly applied to the backup devices. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2024-20263/cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-bus-acl-bypass-5zn9hNJkcnnvd
- https://www.auscert.org.au/bulletins/ESB-2024.0494cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-bus-acl-bypass-5zn9hNJkenisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-bus-acl-bypass-5zn9hNJkVendor Advisorynvd
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