{"cve":"CVE-2021-21971","nvd":{"published":"2022-02-04T23:15:10.830","modified":"2026-06-17T03:36:28.500","status":"Modified","description":"An out-of-bounds write vulnerability exists in the URL_decode functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. A specially-crafted MQTT payload can lead to an out-of-bounds write. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","score":5.9},"cwes":["CWE-787"],"references":["https://talosintelligence.com/vulnerability_reports/TALOS-2021-1406","https://talosintelligence.com/vulnerability_reports/TALOS-2021-1397","https://talosintelligence.com/vulnerability_reports/TALOS-2021-1406"],"products":["sealevel:seaconnect_370w_firmware"],"source":"nvd","synced_at":"2026-10-19T21:27:20.926095847+00:00"},"epss":{"cve":"CVE-2021-21971","score":0.00696,"percentile":0.53048,"date":"2026-10-31"},"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."]}