{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2020-3509 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2020-3509 yet. Limit exposure of the affected software until one is available.","what":"CVE-2020-3509 is a high-severity denial of service vulnerability in Cisco Ios Xe, published on 24 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2020-3509 and fix it if it is affected.\n\nWhat it is: CVE-2020-3509 is a high-severity denial of service vulnerability in Cisco Ios Xe, published on 24 Sep 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2020-3509 in the wild and no public exploit code.\n\nAffected product: Cisco Ios Xe. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2020-3509/ (Markdown: https://insights.sbomify.com/CVE-2020-3509/index.md)","id":"CVE-2020-3509","markdown":"https://insights.sbomify.com/CVE-2020-3509/index.md","name":"CVE-2020-3509","record":{"aliases":["GHSA-w99f-f6h3-qccc"],"analysis":{"component_type":"network_device","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Cisco cBR-8 Router","requires_auth":"none","summary":"Remote unauthenticated attackers can crash Cisco cBR-8 routers by sending malicious DHCPv4 messages, causing a denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"cisco","cpe":[{"product":"ios_xe","vendor":"cisco"}],"cvss":{"score":8.6,"severity":"high","source":"cna","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","version":"3.0"},"cwes":[{"id":"CWE-203","name":"Observable Discrepancy"},{"id":"CWE-388","name":null}],"description":"A vulnerability in the DHCP message handler of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the supervisor to crash, which could result in a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when DHCP version 4 (DHCPv4) messages are parsed. An attacker could exploit this vulnerability by sending a malicious DHCPv4 message to or through a WAN interface of an affected device. A successful exploit could allow the attacker to cause a reload of the affected device. Note: On Cisco cBR-8 Converged Broadband Routers, all of the following are considered WAN interfaces: 10 Gbps Ethernet interfaces 100 Gbps Ethernet interfaces Port channel interfaces that include multiple 10 and/or 100 Gbps Ethernet interfaces","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":null,"headline":"Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers DHCP Denial of Service Vulnerability","id":"CVE-2020-3509","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"cisco:ios_xe","products":["cisco:ios_xe"],"type":"denial_of_service","year":"2020"},"n_packages":0,"n_references":1,"next":{"headline":"Cisco IOS XE Software for Catalyst 9200 Series Switches Umbrella Connector Denial of Service Vulnerability","id":"CVE-2020-3510"},"packages":[],"prev":{"headline":"Denial of service in Cisco IOS XE Software","id":"CVE-2020-3508"},"products":["Cisco IOS XE Software"],"published":"2020-09-24","related":[{"cvss_score":10,"headline":"Cisco IOS XE Web UI Privilege Escalation","id":"CVE-2023-20198","kev_date_added":"2023-10-16","published":"2023-10-16"},{"cvss_score":9.8,"headline":"Cisco IOS Software and Cisco IOS XE Software Quality of Service Remote Code Execution","id":"CVE-2018-0151","kev_date_added":"2022-03-03","published":"2018-03-28"},{"cvss_score":7.2,"headline":"Cisco IOS XE Web UI Command Injection","id":"CVE-2023-20273","kev_date_added":"2023-10-23","published":"2023-10-24"},{"cvss_score":10,"headline":"Hardcoded credentials in Cisco IOS XE Software","id":"CVE-2025-20188","kev_date_added":null,"published":"2025-05-07"},{"cvss_score":10,"headline":"Cisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Remote Code Execution Vulnerability","id":"CVE-2021-34770","kev_date_added":null,"published":"2021-09-23"},{"cvss_score":10,"headline":"Cisco REST API Container for IOS XE Software Authentication Bypass Vulnerability","id":"CVE-2019-12643","kev_date_added":null,"published":"2019-08-28"},{"cvss_score":9.8,"headline":"Cisco IOS XE Software Security Hardening Release","id":"CVE-2026-20272","kev_date_added":null,"published":"2026-08-05"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2024-11-13","vendors":["Cisco"]},"summary":"Remote unauthenticated attackers can crash Cisco cBR-8 routers by sending malicious DHCPv4 messages, causing a denial of service.","url":"https://insights.sbomify.com/CVE-2020-3509/"}