{"id":"JLSEC-2025-218","summary":"An issue was discovered in Mbed TLS before 2.28.1 and 3.x before 3.2.0","details":"An issue was discovered in Mbed TLS before 2.28.1 and 3.x before 3.2.0. In some configurations, an unauthenticated attacker can send an invalid ClientHello message to a DTLS server that causes a heap-based buffer over-read of up to 255 bytes. This can cause a server crash or possibly information disclosure based on error responses. Affected configurations have `MBEDTLS_SSL_DTLS_CLIENT_PORT_REUSE` enabled and `MBEDTLS_SSL_IN_CONTENT_LEN` less than a threshold that depends on the configuration: 258 bytes if using `mbedtls_ssl_cookie_check`, and possibly up to 571 bytes with a custom cookie check function.","modified":"2026-07-25T18:23:58.127067908Z","published":"2025-11-21T15:59:04.054Z","upstream":["CVE-2022-35409"],"database_specific":{"license":"CC-BY-4.0","sources":[{"modified":"2026-06-17T04:51:47.213Z","published":"2022-07-15T14:15:09.840Z","url":"https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2022-35409","html_url":"https://nvd.nist.gov/vuln/detail/CVE-2022-35409","database_specific":{"status":"Modified"},"id":"CVE-2022-35409","imported":"2026-07-17T20:46:13.398Z"}]},"references":[{"type":"WEB","url":"https://github.com/Mbed-TLS/mbedtls/releases"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2022/12/msg00036.html"},{"type":"WEB","url":"https://mbed-tls.readthedocs.io/en/latest/security-advisories/advisories/mbedtls-security-advisory-2022-07.html"}],"affected":[{"package":{"name":"MbedTLS_jll","ecosystem":"Julia","purl":"pkg:julia/MbedTLS_jll?uuid=c8ffd9c3-330d-5841-b78e-0817d7145fa1"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"2.28.2+0"}]}],"database_specific":{"source":"https://github.com/JuliaLang/SecurityAdvisories.jl/tree/generated/osv/2025/JLSEC-2025-218.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H"}]}