{"id":"CVE-2019-11842","aliases":["GHSA-gwf7-vfjf-wf6x","PYSEC-2019-185","PYSEC-2026-2620"],"title":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","summary":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","vendor":"matrix-sydent","product":"matrix-sydent","ecosystem":"pip","affected":["matrix-sydent < 1.0.3","matrix-synapse < 0.99.3.1"],"patched":["matrix-sydent 1.0.3","matrix-synapse 0.99.3.1"],"published":"2022-05-24","updated":"2026-07-13","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-gwf7-vfjf-wf6x","references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2019-11842"},{"url":"https://github.com/advisories/GHSA-gwf7-vfjf-wf6x"},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2019-185.yaml"},{"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"}],"tags":["osv","pip"],"epss":0.01795,"epssPercentile":0.77459,"ingestedAt":"2026-07-13T18:57:58.650Z","slug":"CVE-2019-11842","body":"## Overview\n\nAn 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.\n\n## Affected packages\n\n- `matrix-sydent < 1.0.3`\n- `matrix-synapse < 0.99.3.1`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `matrix-sydent 1.0.3`\n- `matrix-synapse 0.99.3.1`","depth":"twilight","depthScore":42,"depthScoreParts":{"impact":41.3,"likelihood":0.4,"exploitation":0,"ransomware":0},"changes":[]}