{"id":"CVE-2021-42142","aliases":["EUVD-2021-29125","GHSA-q37p-g696-qhwm"],"status":"published","title":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers...","description":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers mishandle the early use of a large epoch number. This vulnerability allows remote attackers to cause a denial of service and false-positive packet drops.","severity":{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.00989,"percentile":0.6274,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-755","CWE-770"],"published":"2024-01-23T00:00:00Z","modified":"2026-06-17T04:09:25Z","products":[{"vendor":"contiki-ng","product":"tinydtls"}],"references":[{"url":"https://github.com/contiki-ng/tinydtls/issues/24","tags":["x_transferred","Issue Tracking","Patch"]},{"url":"https://seclists.org/fulldisclosure/2024/Jan/15","tags":["x_transferred","Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2024/Jan/15"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-42142"},{"url":"https://github.com/advisories/GHSA-q37p-g696-qhwm"}],"sources":{"cve":[{"id":"CVE-2021-42142","description":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers mishandle the early use of a large epoch number. This vulnerability allows remote attackers to cause a denial of service and false-positive packet drops.","status":"published","published":"2024-01-23T00:00:00Z","modified":"2025-06-11T17:09:33.477Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"adp"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:32:58.739039Z"}],"euvd":[{"id":"EUVD-2021-29125","description":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers mishandle the early use of a large epoch number. This vulnerability allows remote attackers to cause a denial of service and false-positive packet drops.","status":"published","published":"2024-01-23T00:00:00Z","modified":"2025-06-11T17:09:33Z","cvss":[{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high"}],"updated_at":"2026-11-02T20:32:24.98161Z"}],"ghsa":[{"id":"GHSA-q37p-g696-qhwm","title":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers...","description":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers mishandle the early use of a large epoch number. This vulnerability allows remote attackers to cause a denial of service and false-positive packet drops.","status":"published","published":"2024-01-24T00:30:32Z","modified":"2025-06-11T18:36:44Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-755","CWE-770"],"updated_at":"2026-11-02T15:02:42.160981Z"}],"nvd":[{"id":"CVE-2021-42142","description":"An issue was discovered in Contiki-NG tinyDTLS through master branch 53a0d97. DTLS servers mishandle the early use of a large epoch number. This vulnerability allows remote attackers to cause a denial of service and false-positive packet drops.","status":"published","published":"2024-01-23T22:15:16.27Z","modified":"2026-06-17T04:09:25.213Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"3.1","score":8.2,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-755","CWE-770"],"updated_at":"2026-11-02T14:07:08.163458Z"}]}}