{"id":"CVE-2020-3496","aliases":["EUVD-2020-24767","GHSA-p3jf-mcx6-q3cr"],"status":"published","title":"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.","severity":{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.01737,"percentile":0.77854,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-20"],"published":"2020-08-26T16:15:54Z","modified":"2026-06-17T03:18:25Z","products":[{"vendor":"cisco","product":"cisco small business 250 series smart switches software"},{"vendor":"cisco","product":"sf200-24_firmware"},{"vendor":"cisco","product":"sf200-24fp_firmware"},{"vendor":"cisco","product":"sf200-24p_firmware"},{"vendor":"cisco","product":"sf200-48_firmware"},{"vendor":"cisco","product":"sf200-48p_firmware"},{"vendor":"cisco","product":"sf250-24_firmware"},{"vendor":"cisco","product":"sf250-24p_firmware"},{"vendor":"cisco","product":"sf250-48_firmware"},{"vendor":"cisco","product":"sf250-48hp_firmware"},{"vendor":"cisco","product":"sf300-08_firmware"},{"vendor":"cisco","product":"sf300-24_firmware"},{"vendor":"cisco","product":"sf300-24mp_firmware"},{"vendor":"cisco","product":"sf300-24p_firmware"},{"vendor":"cisco","product":"sf300-24pp_firmware"},{"vendor":"cisco","product":"sf300-48_firmware"},{"vendor":"cisco","product":"sf300-48p_firmware"},{"vendor":"cisco","product":"sf300-48pp_firmware"},{"vendor":"cisco","product":"sf302-08_firmware"},{"vendor":"cisco","product":"sf302-08mp_firmware"},{"vendor":"cisco","product":"sf302-08mpp_firmware"},{"vendor":"cisco","product":"sf302-08p_firmware"},{"vendor":"cisco","product":"sf302-08pp_firmware"},{"vendor":"cisco","product":"sf350-48_firmware"},{"vendor":"cisco","product":"sf350-48mp_firmware"},{"vendor":"cisco","product":"sf350-48p_firmware"},{"vendor":"cisco","product":"sf500-24_firmware"},{"vendor":"cisco","product":"sf500-24p_firmware"},{"vendor":"cisco","product":"sf500-48_firmware"},{"vendor":"cisco","product":"sf500-48p_firmware"},{"vendor":"cisco","product":"sf550x-24_firmware"},{"vendor":"cisco","product":"sf550x-24mp_firmware"},{"vendor":"cisco","product":"sf550x-24p_firmware"},{"vendor":"cisco","product":"sf550x-48_firmware"},{"vendor":"cisco","product":"sf550x-48mp_firmware"},{"vendor":"cisco","product":"sf550x-48p_firmware"},{"vendor":"cisco","product":"sg200-08_firmware"},{"vendor":"cisco","product":"sg200-08p_firmware"},{"vendor":"cisco","product":"sg200-10fp_firmware"},{"vendor":"cisco","product":"sg200-18_firmware"},{"vendor":"cisco","product":"sg200-26_firmware"},{"vendor":"cisco","product":"sg200-26fp_firmware"},{"vendor":"cisco","product":"sg200-26p_firmware"},{"vendor":"cisco","product":"sg200-50_firmware"},{"vendor":"cisco","product":"sg200-50fp_firmware"},{"vendor":"cisco","product":"sg200-50p_firmware"},{"vendor":"cisco","product":"sg250-08_firmware"},{"vendor":"cisco","product":"sg250-08hp_firmware"},{"vendor":"cisco","product":"sg250-10p_firmware"},{"vendor":"cisco","product":"sg250-18_firmware"},{"vendor":"cisco","product":"sg250-26_firmware"},{"vendor":"cisco","product":"sg250-26hp_firmware"},{"vendor":"cisco","product":"sg250-26p_firmware"},{"vendor":"cisco","product":"sg250-50_firmware"},{"vendor":"cisco","product":"sg250-50hp_firmware"},{"vendor":"cisco","product":"sg250-50p_firmware"},{"vendor":"cisco","product":"sg250x-24_firmware"},{"vendor":"cisco","product":"sg250x-24p_firmware"},{"vendor":"cisco","product":"sg250x-48_firmware"},{"vendor":"cisco","product":"sg250x-48p_firmware"},{"vendor":"cisco","product":"sg300-10_firmware"},{"vendor":"cisco","product":"sg300-10mp_firmware"},{"vendor":"cisco","product":"sg300-10mpp_firmware"},{"vendor":"cisco","product":"sg300-10p_firmware"},{"vendor":"cisco","product":"sg300-10pp_firmware"},{"vendor":"cisco","product":"sg300-10sfp_firmware"},{"vendor":"cisco","product":"sg300-20_firmware"},{"vendor":"cisco","product":"sg300-28_firmware"},{"vendor":"cisco","product":"sg300-28mp_firmware"},{"vendor":"cisco","product":"sg300-28p_firmware"},{"vendor":"cisco","product":"sg300-28pp_firmware"},{"vendor":"cisco","product":"sg300-52_firmware"},{"vendor":"cisco","product":"sg300-52mp_firmware"},{"vendor":"cisco","product":"sg300-52p_firmware"},{"vendor":"cisco","product":"sg350-10_firmware"},{"vendor":"cisco","product":"sg350-10mp_firmware"},{"vendor":"cisco","product":"sg350-10p_firmware"},{"vendor":"cisco","product":"sg350-28_firmware"},{"vendor":"cisco","product":"sg350-28mp_firmware"},{"vendor":"cisco","product":"sg350-28p_firmware"},{"vendor":"cisco","product":"sg350x-24_firmware"},{"vendor":"cisco","product":"sg350x-24mp_firmware"},{"vendor":"cisco","product":"sg350x-24p_firmware"},{"vendor":"cisco","product":"sg350x-48_firmware"},{"vendor":"cisco","product":"sg350x-48mp_firmware"},{"vendor":"cisco","product":"sg350x-48p_firmware"},{"vendor":"cisco","product":"sg350xg-24f_firmware"},{"vendor":"cisco","product":"sg350xg-24t_firmware"},{"vendor":"cisco","product":"sg350xg-2f10_firmware"},{"vendor":"cisco","product":"sg350xg-48t_firmware"},{"vendor":"cisco","product":"sg355-10p_firmware"},{"vendor":"cisco","product":"sg500-28_firmware"},{"vendor":"cisco","product":"sg500-28mpp_firmware"},{"vendor":"cisco","product":"sg500-28p_firmware"},{"vendor":"cisco","product":"sg500-52_firmware"},{"vendor":"cisco","product":"sg500-52mp_firmware"},{"vendor":"cisco","product":"sg500-52p_firmware"},{"vendor":"cisco","product":"sg500x-24_firmware"},{"vendor":"cisco","product":"sg500x-24p_firmware"},{"vendor":"cisco","product":"sg500x-48_firmware"},{"vendor":"cisco","product":"sg500x-48p_firmware"},{"vendor":"cisco","product":"sg500xg-8f8t_firmware"},{"vendor":"cisco","product":"sg550x-24_firmware"},{"vendor":"cisco","product":"sg550x-24mp_firmware"},{"vendor":"cisco","product":"sg550x-24mpp_firmware"},{"vendor":"cisco","product":"sg550x-24p_firmware"},{"vendor":"cisco","product":"sg550x-48_firmware"},{"vendor":"cisco","product":"sg550x-48mp_firmware"},{"vendor":"cisco","product":"sg550x-48p_firmware"},{"vendor":"cisco","product":"sx550x-12f_firmware"},{"vendor":"cisco","product":"sx550x-16ft_firmware"},{"vendor":"cisco","product":"sx550x-24_firmware"},{"vendor":"cisco","product":"sx550x-24f_firmware"},{"vendor":"cisco","product":"sx550x-24ft_firmware"},{"vendor":"cisco","product":"sx550x-52_firmware"}],"references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sbss-ipv6-dos-tsgqbffW","tags":["vendor-advisory","x_refsource_CISCO","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-3496"},{"url":"https://github.com/advisories/GHSA-p3jf-mcx6-q3cr"}],"sources":{"cve":[{"id":"CVE-2020-3496","title":"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.","status":"published","published":"2020-08-26T16:15:54.968Z","modified":"2024-11-13T18:12:35.608Z","cvss":[{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:35:51.923913Z"}],"euvd":[{"id":"EUVD-2020-24767","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.","status":"published","published":"2020-08-26T16:15:54Z","modified":"2024-11-13T18:12:35Z","cvss":[{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"updated_at":"2026-11-03T00:05:01.673157Z"}],"ghsa":[{"id":"GHSA-p3jf-mcx6-q3cr","title":"A vulnerability in the IPv6 packet processing engine of Cisco Small Business Smart and Managed...","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.","status":"published","published":"2022-05-24T17:26:44Z","modified":"2023-01-29T05:03:52Z","cwes":["CWE-20"],"updated_at":"2026-11-02T14:45:25.163341Z"}],"nvd":[{"id":"CVE-2020-3496","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.","status":"published","published":"2020-08-26T17:15:14.21Z","modified":"2026-06-17T03:18:25.8Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"primary"},{"version":"3.0","score":5.3,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"secondary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-20"],"updated_at":"2026-11-02T14:06:13.600965Z"}]}}