{"id":"PYSEC-2026-2620","summary":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","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.","aliases":["CVE-2019-11842","GHSA-gwf7-vfjf-wf6x","PYSEC-2019-185"],"modified":"2026-07-13T16:56:21.055691563Z","published":"2026-07-09T16:49:47.132995Z","references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2019-11842"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-gwf7-vfjf-wf6x"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2019-185.yaml"},{"type":"WEB","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":"PACKAGE","url":"https://pypi.org/project/matrix-sydent"}],"affected":[{"package":{"name":"matrix-sydent","ecosystem":"PyPI","purl":"pkg:pypi/matrix-sydent"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.3"}]}],"database_specific":{"source":"https://github.com/pypa/advisory-database/blob/main/vulns/matrix-sydent/PYSEC-2026-2620.yaml"}}],"schema_version":"1.7.5","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":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"}]}