CVE-2020-3363
mediumpriority · track · 35EPSS 0.018 · 79 %ileEURUUSEPSS · scored 2026-10-28
A vulnerability in the IPv6 packet processing engine of Cisco Small Business Smart and Managed Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of incoming IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet through an affected device. A successful exploit could allow the attacker to cause an unexpected reboot of the switch, leading to a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic is not affected.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Small Business 250 Series Smart Switches Softwarecisco_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 · 5–8.6
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (120)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-sbss-ipv6-dos-3bLk6vACisco Small Business Smart and Managed Switches Denial of Service Vulnerability2020-08-05csaf · cisco_csafUS
A vulnerability in the IPv6 packet processing engine of Cisco Small Business Smart and Managed Switches could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of incoming IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet through an affected device. A successful exploit could allow the attacker to cause an unexpected reboot of the switch, leading to a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic is not affected. Cisco has released software updates that address this vulnerability for devices that have not reached the end of software maintenance. 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 (7)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/48347cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3363cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbss-ipv6-dos-3bLk6vAcnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.2698.2/cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.2698/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbss-ipv6-dos-3bLk6vAenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbss-ipv6-dos-3bLk6vAVendor Advisorynvd
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