Cisco Small Business Smart and Managed Switches Denial of Service Vulnerability

Description

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 the switch management CLI to stop responding, resulting in a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic is not affected.

Scores

EPSS (exploitation in 30 days)

1.7% · top 22% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.

Weakness

• CWE-20 (opens in a new tab)All about CWE-20 and its CVEs

Affected products

• Cisco · Cisco Small Business 250 Series Smart Switches Software

  • affected n/a

What to do

Exploitation: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

References (1)

• 20200819 Cisco Small Business Smart and Managed Switches Denial of Service Vulnerability (opens in a new tab)vendor-advisoryx_refsource_CISCOx_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2020-3496](https://trackcve.app/badge/CVE-2020-3496.svg)](https://trackcve.app/cve/CVE-2020-3496)

Record last updated 13 Nov 2024, 18:12 UTC.