{"id":"CVE-2019-11842","aliases":["DEBIAN-CVE-2019-11842","EUVD-2019-0082","GHSA-gwf7-vfjf-wf6x","PYSEC-2019-185","PYSEC-2026-2620","UBUNTU-CVE-2019-11842","USN-6076-1"],"status":"published","title":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","description":"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.","severity":{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.01795,"percentile":0.78609,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-338"],"published":"2019-05-09T17:06:43Z","modified":"2026-10-24T10:30:46Z","fixes":[{"ecosystem":"PyPI","package":"matrix-sydent","fixed_in":["1.0.3"],"sources":["ghsa","osv"]},{"ecosystem":"PyPI","package":"matrix-synapse","fixed_in":["0.99.3.1"],"sources":["ghsa","osv"]},{"ecosystem":"Ubuntu:Pro:18.04:LTS","package":"matrix-synapse","fixed_in":["0.24.0+dfsg-1ubuntu0.1~esm1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.3"}]}]},{"source":"ghsa","ecosystem":"PyPI","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.99.3.1"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.3"}]}]},{"source":"osv","ecosystem":"PyPI","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.99.3.1"}]}],"versions":["0.33.5","0.33.5.1","0.33.6","0.33.6rc1","0.33.7","0.33.7rc1","0.33.7rc2","0.33.8","0.33.8rc2","0.33.9","0.34.0","0.34.0.1","0.34.0rc1","0.34.0rc2","0.34.1.1","0.99.0","0.99.0rc1","0.99.0rc2","0.99.0rc3","0.99.0rc4","0.99.1","0.99.1.1","0.99.1rc1","0.99.1rc2","0.99.2","0.99.2rc1","0.99.3","0.99.3rc1"]},{"source":"osv","ecosystem":"PyPI","package":"matrix-synapse","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.99.3.1"}]}],"versions":["0.33.5","0.33.5.1","0.33.6","0.33.6rc1","0.33.7","0.33.7rc1","0.33.7rc2","0.33.8","0.33.8rc2","0.33.9","0.34.0","0.34.0.1","0.34.0rc1","0.34.0rc2","0.34.1.1","0.99.0","0.99.0rc1","0.99.0rc2","0.99.0rc3","0.99.0rc4","0.99.1","0.99.1.1","0.99.1rc1","0.99.1rc2","0.99.2","0.99.2rc1","0.99.3","0.99.3rc1"]},{"source":"osv","ecosystem":"PyPI","package":"matrix-sydent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.0.3"}]}]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"matrix-synapse","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"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"matrix-synapse","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"],"bundled":7}],"products":[{"vendor":"matrix","product":"sydent"},{"vendor":"matrix","product":"synapse"}],"references":[{"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":["x_refsource_MISC","x_transferred","Vendor Advisory","advisory","article","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2019-11842","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-gwf7-vfjf-wf6x","tags":["advisory"]},{"url":"https://github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2019-185.yaml","tags":["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","tags":["web"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2019-11842","tags":["advisory"]},{"url":"https://pypi.org/project/matrix-sydent","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2019-11842","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-6076-1","tags":["advisory"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2019-11842","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-10657","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-12291","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-12423","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2018-16515","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-5885","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2019-18835","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2019-11842","description":"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.","status":"published","published":"2019-05-09T17:06:43Z","modified":"2024-08-04T23:03:32.882Z","updated_at":"2026-11-02T14:20:26.416173Z"}],"euvd":[{"id":"EUVD-2019-0082","description":"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.","status":"published","published":"2019-05-09T17:06:43Z","modified":"2024-08-04T23:03:32Z","updated_at":"2026-11-03T02:40:48.505669Z"}],"ghsa":[{"id":"GHSA-gwf7-vfjf-wf6x","title":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","description":"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.","status":"published","published":"2022-05-24T16:45:24Z","modified":"2024-09-30T20:32:30Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"4.0","score":8.7,"vector":"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","level":"high"}],"cwes":["CWE-338"],"updated_at":"2026-11-02T14:38:07.852618Z"}],"nvd":[{"id":"CVE-2019-11842","description":"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.","status":"published","published":"2019-05-09T18:29:07.197Z","modified":"2026-06-17T02:13:43.693Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-338"],"updated_at":"2026-11-02T14:05:13.880207Z"}],"osv":[{"id":"CVE-2019-11842","description":"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.","status":"published","published":"2019-05-09T18:29:07.197Z","modified":"2026-10-24T10:30:46.46657476Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:10.718934Z"},{"id":"DEBIAN-CVE-2019-11842","description":"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.","status":"withdrawn","published":"2019-05-09T18:29:07.197Z","modified":"2026-08-11T20:49:50.148340517Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:45:31.467893Z"},{"id":"GHSA-gwf7-vfjf-wf6x","title":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","description":"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.","status":"published","published":"2022-05-24T16:45:24Z","modified":"2026-07-13T16:42:32.863521797Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"4.0","score":8.7,"vector":"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","level":"high"}],"cwes":["CWE-338"],"updated_at":"2026-11-02T15:46:48.191583Z"},{"id":"PYSEC-2026-2620","title":"matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG","description":"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.","status":"published","published":"2026-07-09T16:49:47.132995Z","modified":"2026-07-13T16:42:32.863521797Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"4.0","score":8.7,"vector":"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","level":"high"}],"updated_at":"2026-11-02T15:52:55.961245Z"},{"id":"UBUNTU-CVE-2019-11842","description":"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.","status":"published","published":"2019-05-09T18:29:00Z","modified":"2026-02-04T03:34:22.923356Z","cvss":[{"version":"3.0","score":7.5,"vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:54:19.202697Z"},{"id":"PYSEC-2019-185","description":"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.","status":"published","published":"2019-05-09T18:29:00Z","modified":"2026-07-13T16:42:32.863521797Z","updated_at":"2026-11-02T15:52:52.192131Z"},{"id":"USN-6076-1","title":"matrix-synapse vulnerabilities","description":"It was discovered that Synapse incorrectly handled certain inputs. If a\nuser or an automated system were tricked into opening a specially crafted\ninput file, a remote attacker could possibly use this issue to cause a\ndenial of service. (CVE-2019-18835, CVE-2018-12291, CVE-2018-10657)\n\nIt was discovered that Synapse incorrectly handled certain inputs. If a\nuser or an automated system were tricked into opening a specially crafted\ninput file, a remote attacker could possibly use this issue to hijack the\nsession. (CVE-2019-11842, CVE-2018-12423)\n\nIt was discovered that Synapse incorrectly handled certain inputs. If a\nuser or an automated system were tricked into opening a specially crafted\ninput file, a remote attacker could possibly use this issue to perform \nspoofing or user impersonation. (CVE-2019-5885, CVE-2018-16515)\n","status":"published","published":"2023-05-16T07:45:08Z","modified":"2026-02-10T04:43:07Z","updated_at":"2026-11-02T16:58:16.738762Z"}]}}