{"id":"UBUNTU-CVE-2021-3405","details":"A flaw was found in libebml before 1.4.2. A heap overflow bug exists in the implementation of EbmlString::ReadData and EbmlUnicodeString::ReadData in libebml.","modified":"2026-09-09T00:30:17.596329572Z","published":"2021-02-23T20:15:00Z","upstream":["CVE-2021-3405"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-3405"},{"type":"REPORT","url":"https://github.com/Matroska-Org/libebml/issues/74"},{"type":"REPORT","url":"https://github.com/Matroska-Org/libebml/pull/76"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-3405"}],"affected":[{"package":{"name":"libebml","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/libebml?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.5-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.4.5-1","binary_name":"libebml5"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3405.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}