{"id":"UBUNTU-CVE-2019-11842","details":"An issue was discovered in Matrix Sydent before 1.0.3 and Synapse before 0.99.3.1. Random number generation is mishandled, which makes it easier for attackers to predict a Sydent authentication token or a Synapse random ID.","modified":"2026-01-30T01:14:44.399220Z","published":"2019-05-09T18:29:00Z","related":["USN-6076-1"],"upstream":["CVE-2019-11842"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2019-11842"},{"type":"REPORT","url":"https://matrix.org/blog/2019/05/03/security-updates-sydent-1-0-3-synapse-0-99-3-1-and-riot-android-0-9-0-0-8-99-0-8-28-a/"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-6076-1"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2019-11842"}],"affected":[{"package":{"name":"matrix-synapse","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/matrix-synapse@0.24.0+dfsg-1ubuntu0.1~esm1?arch=source&distro=esm-apps/bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.24.0+dfsg-1ubuntu0.1~esm1"}]}],"versions":["0.19.2+dfsg-6","0.24.0+dfsg-1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro","binaries":[{"binary_name":"matrix-synapse","binary_version":"0.24.0+dfsg-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2019/UBUNTU-CVE-2019-11842.json"}}],"schema_version":"1.7.3","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]}