{"id":"BIT-nats-2026-33219","revision":null,"records":[{"revision":"61e7aba6bd5746a2a96b14930683e581","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-33219","aliases":[],"title":"NATS is vulnerable to pre-auth DoS through WebSockets client service","description":"NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-server before authentication; this requires sending a corresponding amount of data. This is a milder variant of CVE-2026-27571. That earlier issue was a compression bomb, this vulnerability is not. Attacks against this new issue thus require significant client bandwidth. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable websockets if not required for project deployment.","state":0,"publishedAt":"2026-03-25T19:55:28.363+00:00","modifiedAt":"2026-09-09T12:05:04.261+00:00","affected":[{"ecosystem":"Vendor product","name":"nats-server","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"nats-io\",\n                    \"product\": \"nats-server\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 2.11.15\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \">= 2.12.0-RC.1, < 2.12.6\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":5.3,"severity":"MEDIUM"}],"references":["https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j","https://advisories.nats.io/CVE/secnote-2026-02.txt","https://advisories.nats.io/CVE/secnote-2026-11.txt","https://github.com/advisories/GHSA-qrvq-68c2-7grw"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-33219","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-33219","identifiers":["CVE-2026-33219"]},"retained":false,"historicalAffected":[]},{"revision":"c539f794d45a47d6b8c4d7e8fd2a5784","observedAt":"2026-11-15T09:38:12.74+00:00","statement":{"source":"euvd","id":"EUVD-2026-15970","aliases":["CVE-2026-33219","GHSA-8r68-gvr4-jh7j"],"title":"NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-ser…","description":"NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-server before authentication; this requires sending a corresponding amount of data. This is a milder variant of CVE-2026-27571. That earlier issue was a compression bomb, this vulnerability is not. Attacks against this new issue thus require significant client bandwidth. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable websockets if not required for project deployment.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":null}],"references":["https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j","https://advisories.nats.io/CVE/secnote-2026-02.txt","https://advisories.nats.io/CVE/secnote-2026-11.txt","https://github.com/advisories/GHSA-qrvq-68c2-7grw"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-15970","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Mar 25, 2026, 7:55:28 PM","dateUpdated":"Sep 9, 2026, 12:05:04 PM"},"relatedAdvisories":[{"id":"RHSA-2026:23345","title":"Red Hat Security Advisory: Multicluster Global Hub 1.6.2 security update","vulnerabilityIds":["CVE-2026-4427","CVE-2026-21728","CVE-2026-25679","CVE-2026-27137","CVE-2026-27889","CVE-2026-29785","CVE-2026-32280","CVE-2026-32281","CVE-2026-32282","CVE-2026-32283","CVE-2026-32285","CVE-2026-32286","CVE-2026-33186","CVE-2026-33215","CVE-2026-33216","CVE-2026-33217","CVE-2026-33218","CVE-2026-33219","CVE-2026-33247","CVE-2026-33413","CVE-2026-33487","CVE-2026-33810","CVE-2026-33813","CVE-2026-33997","CVE-2026-34040","CVE-2026-34986","CVE-2026-40890","CVE-2026-41602","CVE-2026-41603","CVE-2026-41604","CVE-2026-41605","CVE-2026-41606","CVE-2026-41607","CVE-2026-41636","CVE-2026-43869"]},{"id":"RHSA-2026:22347","title":"Red Hat Security Advisory: Multicluster Global Hub 1.4.5 security update","vulnerabilityIds":["CVE-2026-4427","CVE-2026-21728","CVE-2026-25679","CVE-2026-27137","CVE-2026-27889","CVE-2026-29785","CVE-2026-32280","CVE-2026-32281","CVE-2026-32282","CVE-2026-32283","CVE-2026-32285","CVE-2026-32286","CVE-2026-33186","CVE-2026-33215","CVE-2026-33216","CVE-2026-33217","CVE-2026-33218","CVE-2026-33219","CVE-2026-33247","CVE-2026-33413","CVE-2026-33487","CVE-2026-33810","CVE-2026-33813","CVE-2026-33997","CVE-2026-34040","CVE-2026-34986","CVE-2026-40890","CVE-2026-41602","CVE-2026-41603","CVE-2026-41604","CVE-2026-41605","CVE-2026-41606","CVE-2026-41607","CVE-2026-41636","CVE-2026-43869"]},{"id":"RHSA-2026:21769","title":"Red Hat Security Advisory: Multicluster Global Hub 1.5.4 security update","vulnerabilityIds":["CVE-2026-4427","CVE-2026-21728","CVE-2026-25679","CVE-2026-27137","CVE-2026-27889","CVE-2026-29785","CVE-2026-32280","CVE-2026-32281","CVE-2026-32282","CVE-2026-32283","CVE-2026-32285","CVE-2026-32286","CVE-2026-33186","CVE-2026-33215","CVE-2026-33216","CVE-2026-33217","CVE-2026-33218","CVE-2026-33219","CVE-2026-33247","CVE-2026-33413","CVE-2026-33487","CVE-2026-33810","CVE-2026-33813","CVE-2026-33997","CVE-2026-34040","CVE-2026-34986","CVE-2026-40890","CVE-2026-41602","CVE-2026-41603","CVE-2026-41604","CVE-2026-41605","CVE-2026-41606","CVE-2026-41607","CVE-2026-41636","CVE-2026-43869"]},{"id":"WID-SEC-W-2026-0858","title":"NATS Server: Mehrere Schwachstellen","vulnerabilityIds":["CVE-2026-33215","CVE-2026-33216","CVE-2026-33217","CVE-2026-33218","CVE-2026-33219","CVE-2026-33222","CVE-2026-33223","CVE-2026-33246","CVE-2026-33247","CVE-2026-33248","CVE-2026-33249"]}],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-15970","identifiers":["EUVD-2026-15970","CVE-2026-33219","GHSA-8r68-gvr4-jh7j"]},"retained":false,"historicalAffected":[]},{"revision":"9da3bd8c86da455bba8a7ee47362193d","observedAt":"2026-10-25T08:17:18.375+00:00","statement":{"source":"nvd","id":"CVE-2026-33219","aliases":[],"title":"NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-ser…","description":"NATS-Server is a High-Performance server for NATS.io, a cloud and edge native messaging system. Prior to versions 2.11.15 and 2.12.6, a malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-server before authentication; this requires sending a corresponding amount of data. This is a milder variant of CVE-2026-27571. That earlier issue was a compression bomb, this vulnerability is not. Attacks against this new issue thus require significant client bandwidth. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable websockets if not required for project deployment.","state":0,"publishedAt":"2026-03-25T20:16:32.777+00:00","modifiedAt":"2026-09-09T13:19:24.173+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":5.3,"severity":"MEDIUM"},{"system":"CVSS 3.1 · 0b0ca135-0b70-47e7-9f44-1890c2a1c46c · Secondary","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5,"severity":"HIGH"}],"references":["https://advisories.nats.io/CVE/secnote-2026-02.txt","https://advisories.nats.io/CVE/secnote-2026-11.txt","https://github.com/advisories/GHSA-qrvq-68c2-7grw","https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j","https://access.redhat.com/errata/RHSA-2026:21769","https://access.redhat.com/errata/RHSA-2026:22347","https://access.redhat.com/errata/RHSA-2026:23345","https://access.redhat.com/security/cve/CVE-2026-33219","https://bugzilla.redhat.com/show_bug.cgi?id=2451445","https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33219.json"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-33219","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Modified","weaknesses":["CWE-770"],"productCriteria":["cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*"],"sourceDates":{"published":"2026-03-25T20:16:32.777","lastModified":"2026-09-09T13:19:24.173"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-33219","identifiers":["CVE-2026-33219"]},"retained":false,"historicalAffected":[]},{"revision":"70ccf71cb8b449ff9129267e28b88d95","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GHSA-8r68-gvr4-jh7j","aliases":["BIT-nats-2026-33219","CVE-2026-33219","GO-2026-4831"],"title":"NATS  is vulnerable to pre-auth DoS through WebSockets client service","description":"### Background\n\nNATS.io is a high performance open source pub-sub distributed communication technology, built for the cloud, on-premise, IoT, and edge computing.\n\nThe nats-server offers a WebSockets client service, used in deployments where browsers are the NATS clients.\n\n### Problem Description\n\nA malicious client which can connect to the WebSockets port can cause unbounded memory use in the nats-server before authentication; this requires sending a corresponding amount of data.\n\nThis is a milder variant of [NATS-advisory-ID 2026-02](https://advisories.nats.io/CVE/secnote-2026-02.txt) (aka CVE-2026-27571; GHSA-qrvq-68c2-7grw).\nThat earlier issue was a compression bomb, this vulnerability is not. Attacks against this new issue thus require significant client bandwidth.\n\n### Affected Versions\n\nAny version before v2.12.6 or v2.11.15\n\n### Workarounds\n\nDisable websockets if not required for project deployment.","state":0,"publishedAt":"2026-03-24T21:46:31+00:00","modifiedAt":"2026-09-10T03:50:38.2452977+00:00","affected":[{"ecosystem":"Go","name":"github.com/nats-io/nats-server/v2","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"2.11.15"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"Go","name":"github.com/nats-io/nats-server/v2","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"2.12.0-RC.1"},{"kind":"fixed","version":"2.12.6"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"Go","name":"github.com/nats-io/nats-server","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j","https://nvd.nist.gov/vuln/detail/CVE-2026-33219","https://advisories.nats.io/CVE/secnote-2026-02.txt","https://advisories.nats.io/CVE/secnote-2026-11.txt","https://github.com/advisories/GHSA-qrvq-68c2-7grw","https://github.com/nats-io/nats-server"],"sourceUrl":"https://github.com/advisories/GHSA-8r68-gvr4-jh7j","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-8r68-gvr4-jh7j","identifiers":["GHSA-8r68-gvr4-jh7j","BIT-nats-2026-33219","CVE-2026-33219","GO-2026-4831"]},"retained":false,"historicalAffected":[]},{"revision":"ef80c4125e704f8da74fd7762ab89f3d","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GO-2026-4831","aliases":["BIT-nats-2026-33219","CVE-2026-33219","GHSA-8r68-gvr4-jh7j"],"title":"NATS is vulnerable to pre-auth DoS through WebSockets client service in github.com/nats-io/nats-server","description":"NATS is vulnerable to pre-auth DoS through WebSockets client service in github.com/nats-io/nats-server","state":0,"publishedAt":"2026-03-26T20:33:05+00:00","modifiedAt":"2026-03-27T18:26:09.072082+00:00","affected":[{"ecosystem":"Go","name":"github.com/nats-io/nats-server","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"Go","name":"github.com/nats-io/nats-server/v2","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"2.11.15"},{"kind":"introduced","version":"2.12.0-RC.1"},{"kind":"fixed","version":"2.12.6"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[],"references":["https://github.com/nats-io/nats-server/security/advisories/GHSA-8r68-gvr4-jh7j","https://advisories.nats.io/CVE/secnote-2026-02.txt","https://advisories.nats.io/CVE/secnote-2026-11.txt","https://github.com/advisories/GHSA-qrvq-68c2-7grw"],"sourceUrl":"https://osv.dev/vulnerability/GO-2026-4831","license":"OSV · upstream source license applies","key":"osv:GO-2026-4831","identifiers":["GO-2026-4831","BIT-nats-2026-33219","CVE-2026-33219","GHSA-8r68-gvr4-jh7j"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-11-15T13:01:41.3445250+00:00","complete":true,"records":1781,"lastAttemptAt":"2026-11-15T13:01:41.344525+00:00","lastSuccessAt":"2026-11-15T13:01:46.2867767+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:46.2867777+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-7de4d7559a5263003f03d9f70577ab06f92ba4178309f26fce53e22a4a959294-24e910670d68255a90dfc1d94d37ac5394a0a43e960361a78142e746e5b8e0e9","complete":true,"records":425790,"lastAttemptAt":"2026-11-15T13:01:16.7308429+00:00","lastSuccessAt":"2026-11-15T13:01:16.7018281+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:16.7308429+00:00","snapshotPublishedAt":"2026-11-15T12:22:01+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-0444dfeaec1f40fea2a42f2c9e01719e","complete":false,"records":13821,"lastAttemptAt":"2026-11-15T13:05:28.9534831+00:00","lastSuccessAt":"2026-11-15T13:05:29.0595405+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:05:29.0595405+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-11-15T13:01:41.3445250+00:00","complete":true,"records":1125,"lastAttemptAt":"2026-11-15T13:01:41.344525+00:00","lastSuccessAt":"2026-11-15T13:01:46.3027206+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:46.3027219+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-00496e381624434cb51cd6ee97f87d5f","complete":true,"records":13833,"lastAttemptAt":"2026-11-15T13:02:04.5706057+00:00","lastSuccessAt":"2026-11-15T13:02:04.555+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:02:04.555+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13874,"expectedIdentifiers":13874,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-64eea06dbd27de8464d5dbce1b78cc794cc59e2d901516ae0d3ea76e624cdae0","complete":true,"records":9955,"lastAttemptAt":"2026-11-15T13:01:38.1237717+00:00","lastSuccessAt":"2026-11-14T13:57:23.1208135+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:38.1237717+00:00","snapshotPublishedAt":"2026-11-14T13:17:57+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-f4424d7d4861b1af1404bd15abcb83f295dcd003412a9340ca99dc8200aa148a","complete":true,"records":2014,"lastAttemptAt":"2026-11-15T13:01:22.067621+00:00","lastSuccessAt":"2026-11-13T19:57:08.2864435+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:22.067621+00:00","snapshotPublishedAt":"2026-11-13T19:33:10+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-6086d649bcb454cdf302d7d9275177bda73550e1b6e446b3520e9b6266d3582c","complete":true,"records":3148,"lastAttemptAt":"2026-11-15T13:01:41.1317031+00:00","lastSuccessAt":"2026-11-15T11:05:17.1034234+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:41.1317031+00:00","snapshotPublishedAt":"2026-11-15T10:03:04+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-ff18f36f13fcca3a20a3fb9274b59b8872d18869a99071730e1e79b625c8f612","complete":true,"records":232475,"lastAttemptAt":"2026-11-15T13:01:28.8971106+00:00","lastSuccessAt":"2026-11-15T11:05:10.4195883+00:00","error":null,"lastVerifiedAt":"2026-11-15T13:01:28.8971106+00:00","snapshotPublishedAt":"2026-11-15T10:33:06+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}