{"id":"CVE-2019-11808","aliases":["EUVD-2019-0451","GHSA-54mg-vgrp-mwx9"],"status":"published","title":"Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Ratpack","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","severity":{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"low","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-09","score":0.01315,"percentile":0.70958,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-338"],"published":"2019-05-07T06:53:16Z","modified":"2026-10-20T13:55:53Z","fixes":[{"ecosystem":"Maven","package":"io.ratpack:ratpack-session","fixed_in":["1.6.1"],"sources":["ghsa","osv"]},{"ecosystem":"Maven","package":"io.ratpack:ratpack-java","fixed_in":["1.6.1"],"sources":["ghsa","osv"]},{"ecosystem":"Maven","package":"io.ratpack:ratpack-groovy","fixed_in":["1.6.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Maven","package":"io.ratpack:ratpack-session","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.1"}]}]},{"source":"ghsa","ecosystem":"Maven","package":"io.ratpack:ratpack-java","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.1"}]}]},{"source":"ghsa","ecosystem":"Maven","package":"io.ratpack:ratpack-groovy","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.1"}]}]},{"source":"osv","ecosystem":"Maven","package":"io.ratpack:ratpack-session","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.1"}]}],"versions":["0.9.0","0.9.1","0.9.10","0.9.11","0.9.12","0.9.13","0.9.14","0.9.15","0.9.16","0.9.17","0.9.18","0.9.19","0.9.2","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","1.0.0","1.0.0-rc-1","1.0.0-rc-2","1.0.0-rc-3","1.1.0","1.1.1","1.2.0","1.2.0-RC-1","1.2.0-rc-2","1.3.0","1.3.0-rc-1","1.3.0-rc-2","1.3.1","1.3.2","1.3.3","1.4.0","1.4.0-rc-1","1.4.0-rc-2","1.4.0-rc-3","1.4.1","1.4.2","1.4.3","1.4.4","1.4.5","1.4.6","1.5.0","1.5.1","1.5.2","1.5.3","1.5.4","1.6.0","1.6.0-rc-1","1.6.0-rc-2","1.6.0-rc-3","1.6.0-rc-4"]},{"source":"osv","ecosystem":"Maven","package":"io.ratpack:ratpack-java","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.1"}]}]},{"source":"osv","ecosystem":"Maven","package":"io.ratpack:ratpack-groovy","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.6.1"}]}],"versions":["0.9.0","0.9.1","0.9.10","0.9.11","0.9.12","0.9.13","0.9.14","0.9.15","0.9.16","0.9.17","0.9.18","0.9.19","0.9.2","0.9.3","0.9.4","0.9.5","0.9.6","0.9.7","0.9.8","0.9.9","1.0.0","1.0.0-rc-1","1.0.0-rc-2","1.0.0-rc-3","1.1.0","1.1.1","1.2.0","1.2.0-RC-1","1.2.0-rc-2","1.3.0","1.3.0-rc-1","1.3.0-rc-2","1.3.1","1.3.2","1.3.3","1.4.0","1.4.0-rc-1","1.4.0-rc-2","1.4.0-rc-3","1.4.1","1.4.2","1.4.3","1.4.4","1.4.5","1.4.6","1.5.0","1.5.1","1.5.2","1.5.3","1.5.4","1.6.0","1.6.0-rc-1","1.6.0-rc-2","1.6.0-rc-3","1.6.0-rc-4"]}],"products":[{"vendor":"ratpack_project","product":"ratpack"}],"references":[{"url":"https://github.com/ratpack/ratpack/releases/tag/v1.6.1","tags":["x_refsource_MISC","x_transferred","Release Notes","Third Party Advisory","advisory","web"]},{"url":"https://github.com/ratpack/ratpack/commit/f2b63eb82dd71194319fd3945f5edf29b8f3a42d","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://github.com/ratpack/ratpack/issues/1448","tags":["x_refsource_MISC","x_transferred","Patch","Third Party Advisory","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2019-11808","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-54mg-vgrp-mwx9"}],"sources":{"cve":[{"id":"CVE-2019-11808","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","status":"published","published":"2019-05-07T06:53:16Z","modified":"2024-08-04T23:03:32.877Z","updated_at":"2026-11-02T14:20:26.416173Z"}],"euvd":[{"id":"EUVD-2019-0451","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","status":"published","published":"2019-05-07T06:53:16Z","modified":"2024-08-04T23:03:32Z","updated_at":"2026-11-03T02:40:48.505669Z"}],"ghsa":[{"id":"GHSA-54mg-vgrp-mwx9","title":"Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Ratpack","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","status":"published","published":"2019-05-14T04:01:37Z","modified":"2023-02-01T05:01:57Z","cvss":[{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"cwes":["CWE-338"],"updated_at":"2026-11-02T14:36:30.61364Z"}],"nvd":[{"id":"CVE-2019-11808","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","status":"published","published":"2019-05-07T07:29:05.167Z","modified":"2026-06-17T02:13:39.21Z","cvss":[{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"low","assessor":"primary"},{"version":"2.0","score":4.3,"vector":"AV:N/AC:M/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-2019-11808","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","status":"published","published":"2019-05-07T07:29:05.167Z","modified":"2026-10-20T13:55:53.188908229Z","cvss":[{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"updated_at":"2026-11-02T15:44:10.718934Z"},{"id":"GHSA-54mg-vgrp-mwx9","title":"Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Ratpack","description":"Ratpack versions before 1.6.1 generate a session ID using a cryptographically weak PRNG in the JDK's ThreadLocalRandom. This means that if an attacker can determine a small window for the server start time and obtain a session ID value, they can theoretically determine the sequence of session IDs.","status":"published","published":"2019-05-14T04:01:37Z","modified":"2023-11-08T04:01:02.010246Z","cvss":[{"version":"3.0","score":3.7,"vector":"CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","level":"low"}],"cwes":["CWE-338"],"updated_at":"2026-11-02T15:46:37.864461Z"}]}}