{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-21727 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-21727 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-21727 is a high-severity denial of service vulnerability in \u003cZXHN F623\u003e, published on 29 Mar 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-21727 and fix it if it is affected.\n\nWhat it is: CVE-2021-21727 is a high-severity denial of service vulnerability in \u003cZXHN F623\u003e, published on 29 Mar 2021. 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-2021-21727 in the wild and no public exploit code.\n\nAffected product: \u003cZXHN F623\u003e. 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-2021-21727/ (Markdown: https://insights.sbomify.com/CVE-2021-21727/index.md)","id":"CVE-2021-21727","markdown":"https://insights.sbomify.com/CVE-2021-21727/index.md","name":"CVE-2021-21727","record":{"aliases":["GHSA-8q85-4h38-w789"],"analysis":{"component_type":"network_device","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"ZTE home router","requires_auth":"none","summary":"Remote attackers can cause denial of service on ZTE ZXHN F623 devices by sending crafted IPv6 packets, requiring firmware updates to mitigate.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"zte","cpe":[{"product":"zxhn_f623_firmware","vendor":"zte"}],"cvss":{"score":7.5,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[],"description":"A ZTE product has a DoS vulnerability. A remote attacker can amplify traffic by sending carefully constructed IPv6 packets to the affected devices, which eventually leads to device denial of service. This affects:\u003cZXHN F623\u003e\u003cAll versions up to V6.0.0P3T33\u003e","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 \u003cZXHN F623\u003e","id":"CVE-2021-21727","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2021"},"n_packages":0,"n_references":1,"next":{"headline":"Denial of service in ZXA10 C300M","id":"CVE-2021-21728"},"packages":[],"prev":{"headline":"Denial of service in \u003cZXONE 9700 , ZXONE 8700, ZXONE 19700\u003e","id":"CVE-2021-21726"},"products":["\u003cZXHN F623\u003e"],"published":"2021-03-29","related":[],"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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["n/a"]},"summary":"Remote attackers can cause denial of service on ZTE ZXHN F623 devices by sending crafted IPv6 packets, requiring firmware updates to mitigate.","url":"https://insights.sbomify.com/CVE-2021-21727/"}