{"id":"CVE-2021-4234","aliases":["EUVD-2021-34091","GHSA-qvww-9jm9-f3pm"],"status":"published","title":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a...","description":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a response to a reset packet sent from the client which the client again does not respond to, resulting in a limited amplification attack.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.00916,"percentile":0.60478,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-406"],"published":"2022-07-06T19:10:17Z","modified":"2026-06-17T04:19:19Z","products":[{"vendor":"openvpn","product":"openvpn_access_server"}],"references":[{"url":"https://openvpn.net/vpn-server-resources/release-notes/#openvpn-access-server-2-11-0","tags":["x_refsource_MISC","x_transferred","Release Notes","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-4234"},{"url":"https://github.com/advisories/GHSA-qvww-9jm9-f3pm"}],"sources":{"cve":[{"id":"CVE-2021-4234","description":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a response to a reset packet sent from the client which the client again does not respond to, resulting in a limited amplification attack.","status":"published","published":"2022-07-06T19:10:17Z","modified":"2024-08-03T17:23:09.056Z","cwes":["CWE-406"],"updated_at":"2026-11-02T14:33:07.697752Z"}],"euvd":[{"id":"EUVD-2021-34091","description":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a response to a reset packet sent from the client which the client again does not respond to, resulting in a limited amplification attack.","status":"published","published":"2022-07-06T19:10:17Z","modified":"2024-08-03T17:23:09Z","updated_at":"2026-11-03T03:25:10.418596Z"}],"ghsa":[{"id":"GHSA-qvww-9jm9-f3pm","title":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a...","description":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a response to a reset packet sent from the client which the client again does not respond to, resulting in a limited amplification attack.","status":"published","published":"2022-07-07T00:00:23Z","modified":"2023-01-27T05:05:13Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T14:42:38.917516Z"}],"nvd":[{"id":"CVE-2021-4234","description":"OpenVPN Access Server 2.10 and prior versions are susceptible to resending multiple packets in a response to a reset packet sent from the client which the client again does not respond to, resulting in a limited amplification attack.","status":"published","published":"2022-07-06T20:15:08.127Z","modified":"2026-06-17T04:19:19.24Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-406"],"updated_at":"2026-11-02T14:07:06.501652Z"}]}}