{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-20084", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-20084", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-03-25T16:02:39.119Z", "updatedAt": "2026-03-26T17:35:50.008Z", "importedAt": "2026-10-24T01:57:55.771Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": null, "summary": "A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be forwarded between VLANs, resulting in a denial of service (DoS) condition. \r\n\r This vulnerability is due to improper handling of BOOTP packets on Cisco Catalyst 9000 Series Switches. An attacker could exploit this vulnerability by sending BOOTP request packets to an affected device. A successful exploit could allow an attacker to forward BOOTP packets from one VLAN to another, resulting in BOOTP VLAN leakage and potentially leading to high CPU utilization. This makes the device unreachable (either through console or remote management) and unable to forward traffic, resulting in a DoS condition. \r\n\r Note: This vulnerability can be exploited with either unicast or broadcast BOOTP packets.\r\n\r There are workarounds that address this vulnerability.", "affected": [ { "vendor": "Cisco", "product": "Cisco IOS XE Software", "versions": [ { "version": "16.6.1", "status": "affected" }, { "version": "16.6.2", "status": "affected" }, { "version": "16.6.3", "status": "affected" }, { "version": "16.6.4", "status": "affected" }, { "version": "16.6.5", "status": "affected" }, { "version": "16.6.4a", "status": "affected" }, { "version": "16.6.6", "status": "affected" }, { "version": "16.6.7", "status": "affected" }, { "version": "16.6.8", "status": "affected" }, { "version": "16.6.9", "status": "affected" }, { "version": "16.6.10", "status": "affected" }, { "version": "16.7.1", "status": "affected" }, { "version": "16.8.1", "status": "affected" }, { "version": "16.8.1a", "status": "affected" }, { "version": "16.8.1s", "status": "affected" }, { "version": "16.9.1", "status": "affected" }, { "version": "16.9.2", "status": "affected" }, { "version": "16.9.1s", "status": "affected" }, { "version": "16.9.3", "status": "affected" }, { "version": "16.9.4", "status": "affected" }, { "version": "16.9.5", "status": "affected" }, { "version": "16.9.6", "status": "affected" }, { "version": "16.9.7", "status": "affected" }, { "version": "16.9.8", "status": "affected" }, { "version": "16.10.1", "status": "affected" }, { "version": "16.10.1s", "status": "affected" }, { "version": "16.10.1e", "status": "affected" }, { "version": "16.11.1", "status": "affected" }, { "version": "16.11.1b", "status": "affected" }, { "version": "16.11.1s", "status": "affected" }, { "version": "16.12.1", "status": "affected" }, { "version": "16.12.1s", "status": "affected" }, { "version": "16.12.1c", "status": "affected" }, { "version": "16.12.2", "status": "affected" }, { "version": "16.12.3", "status": "affected" }, { "version": "16.12.8", "status": "affected" }, { "version": "16.12.2s", "status": "affected" }, { "version": "16.12.4", "status": "affected" }, { "version": "16.12.3s", "status": "affected" }, { "version": "16.12.3a", "status": "affected" }, { "version": "16.12.4a", "status": "affected" }, { "version": "16.12.5", "status": "affected" }, { "version": "16.12.6", "status": "affected" }, { "version": "16.12.5b", "status": "affected" }, { "version": "16.12.6a", "status": "affected" }, { "version": "16.12.7", "status": "affected" }, { "version": "17.1.1", "status": "affected" }, { "version": "17.1.1s", "status": "affected" }, { "version": "17.1.1t", "status": "affected" }, { "version": "17.1.3", "status": "affected" }, { "version": "17.2.1", "status": "affected" }, { "version": "17.2.1a", "status": "affected" }, { "version": "17.3.1", "status": "affected" }, { "version": "17.3.2", "status": "affected" }, { "version": "17.3.3", "status": "affected" }, { "version": "17.3.2a", "status": "affected" }, { "version": "17.3.4", "status": "affected" }, { "version": "17.3.5", "status": "affected" }, { "version": "17.3.6", "status": "affected" }, { "version": "17.3.7", "status": "affected" }, { "version": "17.3.8", "status": "affected" }, { "version": "17.3.8a", "status": "affected" }, { "version": "17.4.1", "status": "affected" }, { "version": "17.5.1", "status": "affected" }, { "version": "17.6.1", "status": "affected" }, { "version": "17.6.2", "status": "affected" }, { "version": "17.6.3", "status": "affected" }, { "version": "17.6.1y", "status": "affected" }, { "version": "17.6.4", "status": "affected" }, { "version": "17.6.5", "status": "affected" }, { "version": "17.6.6", "status": "affected" }, { "version": "17.6.6a", "status": "affected" }, { "version": "17.6.5a", "status": "affected" }, { "version": "17.6.7", "status": "affected" }, { "version": "17.6.8", "status": "affected" }, { "version": "17.7.1", "status": "affected" }, { "version": "17.10.1", "status": "affected" }, { "version": "17.10.1b", "status": "affected" }, { "version": "17.8.1", "status": "affected" }, { "version": "17.9.1", "status": "affected" }, { "version": "17.9.2", "status": "affected" }, { "version": "17.9.3", "status": "affected" }, { "version": "17.9.4", "status": "affected" }, { "version": "17.9.5", "status": "affected" }, { "version": "17.9.4a", "status": "affected" }, { "version": "17.9.6", "status": "affected" }, { "version": "17.9.6a", "status": "affected" }, { "version": "17.9.7", "status": "affected" }, { "version": "17.9.8", "status": "affected" }, { "version": "17.11.1", "status": "affected" }, { "version": "17.12.1", "status": "affected" }, { "version": "17.12.2", "status": "affected" }, { "version": "17.12.3", "status": "affected" }, { "version": "17.12.4", "status": "affected" }, { "version": "17.12.5", "status": "affected" }, { "version": "17.12.1z5", "status": "affected" }, { "version": "17.13.1", "status": "affected" }, { "version": "17.14.1", "status": "affected" }, { "version": "17.15.1", "status": "affected" }, { "version": "17.15.2", "status": "affected" }, { "version": "17.15.3", "status": "affected" }, { "version": "17.15.2b", "status": "affected" }, { "version": "17.15.4", "status": "affected" }, { "version": "17.15.4d", "status": "affected" }, { "version": "17.16.1", "status": "affected" }, { "version": "17.17.1", "status": "affected" }, { "version": "17.18.1", "status": "affected" } ] } ] } } }