{"cve":"CVE-2021-21727","nvd":{"published":"2021-03-29T16:15:13.133","modified":"2026-06-17T03:36:02.940","status":"Modified","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:<ZXHN F623><All versions up to V6.0.0P3T33>","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":[],"references":["https://support.zte.com.cn/support/news/LoopholeInfoDetail.aspx?newsId=1014744","https://support.zte.com.cn/support/news/LoopholeInfoDetail.aspx?newsId=1014744"],"products":["zte:zxhn_f623_firmware"],"source":"nvd","synced_at":"2026-10-19T21:17:01.373894544+00:00"},"epss":{"cve":"CVE-2021-21727","score":0.01437,"percentile":0.7314,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}