{"id":"UBUNTU-CVE-2025-65497","details":"NULL pointer dereference in coap_dtls_generate_cookie() in src/coap_openssl.c in OISM libcoap 4.3.5 allows remote attackers to cause a denial of service via a crafted DTLS handshake that triggers SSL_get_SSL_CTX() to return NULL.","modified":"2026-01-20T18:38:56.970309Z","published":"2025-11-24T14:15:00Z","upstream":["CVE-2025-65497"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2025-65497"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2025-65497"},{"type":"REPORT","url":"https://github.com/obgm/libcoap/issues/1745"},{"type":"REPORT","url":"https://github.com/obgm/libcoap/pull/1750"}],"affected":[{"package":{"name":"libcoap","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libcoap@4.1.2-1?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.2-1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.1.2-1","binary_name":"libcoap-1-0"},{"binary_version":"4.1.2-1","binary_name":"libcoap-1-0-bin"},{"binary_version":"4.1.2-1","binary_name":"libcoap-1-0-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-65497.json"}},{"package":{"name":"libcoap2","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libcoap2@4.2.1-1?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.0-2","4.2.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.2.1-1","binary_name":"libcoap2"},{"binary_version":"4.2.1-1","binary_name":"libcoap2-bin"},{"binary_version":"4.2.1-1","binary_name":"libcoap2-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-65497.json"}},{"package":{"name":"libcoap2","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libcoap2@4.2.1-1build1?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.1-1","4.2.1-1build1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.2.1-1build1","binary_name":"libcoap2"},{"binary_version":"4.2.1-1build1","binary_name":"libcoap2-bin"},{"binary_version":"4.2.1-1build1","binary_name":"libcoap2-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-65497.json"}},{"package":{"name":"libcoap3","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libcoap3@4.3.0-2build1?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.0-2","4.3.0-2build1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.3.0-2build1","binary_name":"libcoap3"},{"binary_version":"4.3.0-2build1","binary_name":"libcoap3-bin"},{"binary_version":"4.3.0-2build1","binary_name":"libcoap3-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-65497.json"}},{"package":{"name":"libcoap3","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/libcoap3@4.3.4-1.1build4?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.1-2","4.3.3-1","4.3.4-1","4.3.4-1.1build2","4.3.4-1.1build3","4.3.4-1.1build4"],"ecosystem_specific":{"binaries":[{"binary_version":"4.3.4-1.1build4","binary_name":"libcoap3-bin"},{"binary_version":"4.3.4-1.1build4","binary_name":"libcoap3-dev"},{"binary_version":"4.3.4-1.1build4","binary_name":"libcoap3t64"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-65497.json"}},{"package":{"name":"libcoap3","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/libcoap3@4.3.4-1.1build4?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.4-1.1build4"],"ecosystem_specific":{"binaries":[{"binary_version":"4.3.4-1.1build4","binary_name":"libcoap3-bin"},{"binary_version":"4.3.4-1.1build4","binary_name":"libcoap3-dev"},{"binary_version":"4.3.4-1.1build4","binary_name":"libcoap3t64"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-65497.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L"},{"type":"Ubuntu","score":"medium"}]}