{"cve":"CVE-2021-3321","nvd":{"published":"2021-10-12T22:15:07.967","modified":"2026-06-17T04:04:56.270","status":"Modified","description":"Integer Underflow in Zephyr in IEEE 802154 Fragment Reassembly Header Removal. Zephyr versions >= >=2.4.0 contain Integer Overflow to Buffer Overflow (CWE-680). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-w44j-66g7-xw99","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-191","CWE-680"],"references":["http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-w44j-66g7-xw99","http://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-w44j-66g7-xw99"],"products":["zephyrproject:zephyr"],"source":"nvd","synced_at":"2026-10-19T21:24:39.218183596+00:00"},"epss":{"cve":"CVE-2021-3321","score":0.00761,"percentile":0.55319,"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."]}