{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-33218", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-03-17T23:23:58.314Z", "datePublished": "2026-03-25T19:53:12.075Z", "dateUpdated": "2026-03-25T19:53:12.075Z"}, "containers": {"cna": {"title": "NATS has pre-auth server panic via leafnode handling", "problemTypes": [{"descriptions": [{"cweId": "CWE-20", "lang": "en", "description": "CWE-20: Improper Input Validation", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339"}, {"name": "https://advisories.nats.io/CVE/secnote-2026-10.txt", "tags": ["x_refsource_MISC"], "url": "https://advisories.nats.io/CVE/secnote-2026-10.txt"}], "affected": [{"vendor": "nats-io", "product": "nats-server", "versions": [{"version": "< < 2.11.15", "status": "affected"}, {"version": ">= 2.12.0-RC.1, < 2.12.6", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-03-25T19:53:12.075Z"}, "descriptions": [{"lang": "en", "value": "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 client which can connect to the leafnode port can crash the nats-server with a certain malformed message pre-authentication. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable leafnode support if not needed or restrict network connections to the leafnode port, if plausible without compromising the service offered."}], "source": {"advisory": "GHSA-vprv-35vv-q339", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "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 client which can connect to the leafnode port can crash the nats-server with a certain malformed message pre-authentication. Versions 2.11.15 and 2.12.6 contain a fix. As a workaround, disable leafnode support if not needed or restrict network connections to the leafnode port, if plausible without compromising the service offered."}], "id": "CVE-2026-33218", "lastModified": "2026-03-25T20:16:32.623", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-03-25T20:16:32.623", "references": [{"source": "security-advisories@github.com", "url": "https://advisories.nats.io/CVE/secnote-2026-10.txt"}, {"source": "security-advisories@github.com", "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-20"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}