{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2016-6421 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2016-6421 yet. Limit exposure of the affected software until one is available.","what":"CVE-2016-6421 is a medium-severity denial of service vulnerability in Cisco Ios Xr, published on 5 Oct 2016. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2016-6421 and fix it if it is affected.\n\nWhat it is: CVE-2016-6421 is a medium-severity denial of service vulnerability in Cisco Ios Xr, published on 5 Oct 2016. 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-2016-6421 in the wild and no public exploit code.\n\nAffected product: Cisco Ios Xr. 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-2016-6421/ (Markdown: https://insights.sbomify.com/CVE-2016-6421/index.md)","id":"CVE-2016-6421","markdown":"https://insights.sbomify.com/CVE-2016-6421/index.md","name":"CVE-2016-6421","record":{"aliases":["GHSA-p9ch-7c57-q9hh"],"analysis":{"component_type":"network_device","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Cisco IOS XR","requires_auth":"none","summary":"Remote attackers can cause a denial of service by sending crafted OSPF Link State Advertisement updates to Cisco IOS XR devices.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"cisco","cpe":[{"product":"ios_xr","vendor":"cisco"}],"cvss":{"score":5.3,"severity":"medium","source":"nvd","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.0"},"cwes":[{"id":"CWE-399","name":null}],"description":"Cisco IOS XR 5.2.2 allows remote attackers to cause a denial of service (process restart) via a crafted OSPF Link State Advertisement (LSA) update, aka Bug ID CSCvb05643.","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":"Denial of service in n/a","id":"CVE-2016-6421","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"cisco:ios_xr","products":["cisco:ios_xr"],"type":"denial_of_service","year":"2016"},"n_packages":0,"n_references":3,"next":{"headline":"Security feature bypass in n/a","id":"CVE-2016-6422"},"packages":[],"prev":{"headline":"Missing authorization in n/a","id":"CVE-2016-6420"},"products":["n/a"],"published":"2016-10-05","related":[{"cvss_score":8.8,"headline":"Cisco IOS XR Software Discovery Protocol Format String","id":"CVE-2020-3118","kev_date_added":"2021-11-03","published":"2020-02-05"},{"cvss_score":8.6,"headline":"Cisco IOS XR Software DVMRP Memory Exhaustion","id":"CVE-2020-3569","kev_date_added":"2021-11-03","published":"2020-09-23"},{"cvss_score":8.6,"headline":"Cisco IOS XR Software DVMRP Memory Exhaustion","id":"CVE-2020-3566","kev_date_added":"2021-11-03","published":"2020-08-29"},{"cvss_score":7.5,"headline":"Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service","id":"CVE-2010-3035","kev_date_added":"2022-03-25","published":"2010-08-30"},{"cvss_score":6.5,"headline":"Cisco IOS XR Open Port","id":"CVE-2022-20821","kev_date_added":"2022-05-23","published":"2022-05-26"},{"cvss_score":5.9,"headline":"Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service","id":"CVE-2009-2055","kev_date_added":"2022-03-25","published":"2009-08-19"},{"cvss_score":9.8,"headline":"Cisco IOS XR Software Security Hardening Release: September 2026","id":"CVE-2026-20274","kev_date_added":null,"published":"2026-09-02"}],"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-06","vendors":["n/a"]},"summary":"Remote attackers can cause a denial of service by sending crafted OSPF Link State Advertisement updates to Cisco IOS XR devices.","url":"https://insights.sbomify.com/CVE-2016-6421/"}