{"id":"CVE-2026-58208","aliases":["AZL-92247","DEBIAN-CVE-2026-58208","EUVD-2026-42391","GHSA-p957-7v2w-g93g","UBUNTU-CVE-2026-58208"],"status":"published","title":"NATS Server: MQTT-over-WebSocket Path Can Crash WebSocket-Only JetStream Servers Before MQTT Is Enabled","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","severity":{"version":"3.1","score":6.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.006,"percentile":0.49075,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-248"],"published":"2026-07-08T20:17:39Z","modified":"2026-11-05T05:40:51Z","fixes":[{"ecosystem":"Azure Linux:3","package":"telegraf","fixed_in":["1.31.0-27"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"nats-server","fixed_in":["2.14.3-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Azure Linux:3","package":"telegraf","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.31.0-27"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.1-1","2.10.16-1","2.10.18-1","2.10.24-1","2.10.27-1","2.10.3-1","2.10.4-1","2.10.7-1","2.12.4-1","2.12.6-1","2.14.1-1","2.14.3-1","2.14.6-1","2.15.1-1","2.9.10-1","2.9.19-1"]},{"source":"osv","ecosystem":"Debian:13","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.27-1","2.12.4-1","2.12.6-1","2.14.1-1","2.14.3-1","2.14.6-1","2.15.1-1"]},{"source":"osv","ecosystem":"Debian:14","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.14.3-1"}]}],"versions":["2.10.27-1","2.12.4-1","2.12.6-1","2.14.1-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.9.19-1build1","2.10.3-1","2.10.4-1","2.10.7-1","2.10.7-1ubuntu0.1","2.10.7-1ubuntu0.2","2.10.7-1ubuntu0.3"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.24-1","2.10.27-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.27-1build1","2.14.1-1","2.14.3-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:26.04:LTS","package":"nats-server","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10.27-1","2.10.27-1build1","2.10.27-1ubuntu0.26.04.1~esm1"]}],"products":[{"vendor":"linuxfoundation","product":"nats-server"},{"vendor":"nats-io","product":"nats-server"}],"references":[{"url":"https://github.com/nats-io/nats-server/security/advisories/GHSA-p957-7v2w-g93g","tags":["x_refsource_CONFIRM","Mitigation","Vendor Advisory","advisory","report"]},{"url":"https://github.com/nats-io/nats-server/commit/73b3dd9a5ea0fa7bf08b702338676355b29b5fb4","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/nats-io/nats-server/commit/837536b98b3a9280b993282155ff2bdd3ca38c30","tags":["x_refsource_MISC","Patch","fix"]},{"url":"https://github.com/nats-io/nats-server/releases/tag/v2.12.12","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://github.com/nats-io/nats-server/releases/tag/v2.14.3","tags":["x_refsource_MISC","Release Notes","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58208","tags":["web","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58208.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-58208","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-58208","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-58208","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-58208","title":"NATS Server: MQTT-over-WebSocket Path Can Crash WebSocket-Only JetStream Servers Before MQTT Is Enabled","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T20:17:39.187Z","modified":"2026-07-09T14:04:28.045Z","cvss":[{"version":"3.1","score":6.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-248"],"updated_at":"2026-11-02T13:47:39.876248Z"}],"euvd":[{"id":"EUVD-2026-42391","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T20:17:39Z","modified":"2026-07-09T14:04:28Z","cvss":[{"version":"3.1","score":6.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T18:20:04.523855Z"}],"nvd":[{"id":"CVE-2026-58208","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T21:16:52.44Z","modified":"2026-10-25T17:10:00.197Z","cvss":[{"version":"3.1","score":6.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"medium","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-248"],"updated_at":"2026-11-02T14:12:28.4135Z"}],"osv":[{"id":"CVE-2026-58208","title":"NATS Server: MQTT-over-WebSocket Path Can Crash WebSocket-Only JetStream Servers Before MQTT Is Enabled","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T20:17:39.187Z","modified":"2026-10-28T02:31:13.431665488Z","cvss":[{"version":"3.1","score":6.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-248"],"updated_at":"2026-11-02T15:45:12.016252Z"},{"id":"DEBIAN-CVE-2026-58208","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T21:16:52.44Z","modified":"2026-10-26T12:02:37.389129591Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:57.590991Z"},{"id":"UBUNTU-CVE-2026-58208","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T21:16:00Z","modified":"2026-10-17T12:59:13.501065839Z","cvss":[{"version":"3.1","score":6.8,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"medium"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T16:56:41.911783Z"},{"id":"AZL-92247","title":"CVE-2026-58208 affecting package telegraf for versions less than 1.31.0-27","description":"NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a WebSocket listener could route requests for the MQTT-over-WebSocket path into MQTT handling even when MQTT was not configured, allowing an unauthenticated client with access to the WebSocket listener to reach uninitialized MQTT state and crash the server process. This issue is fixed in versions 2.14.3 and 2.12.12.","status":"published","published":"2026-07-08T21:16:52Z","modified":"2026-11-05T05:40:51Z","updated_at":"2026-11-05T16:41:25.880689Z"}]}}