{"cve":"CVE-2021-42146","nvd":{"published":"2024-01-24T19:15:08.483","modified":"2026-06-17T04:09:25.910","status":"Modified","description":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers allow remote attackers to reuse the same epoch number within two times the TCP maximum segment lifetime, which is prohibited in RFC6347. This vulnerability allows remote attackers to obtain sensitive application (data of connected clients).","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","score":7.5},"cwes":["CWE-755","CWE-303"],"references":["https://seclists.org/fulldisclosure/2024/Jan/19","http://seclists.org/fulldisclosure/2024/Jan/19","https://seclists.org/fulldisclosure/2024/Jan/19"],"products":["contiki-ng:tinydtls"],"source":"nvd","synced_at":"2026-10-19T21:44:57.175229480+00:00"},"epss":{"cve":"CVE-2021-42146","score":0.00662,"percentile":0.51651,"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."]}