FKIE_CVE-2026-33218

Vulnerability from fkie_nvd - Published: 2026-03-25 20:16 - Updated: 2026-03-26 17:15
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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.
References
security-advisories@github.comhttps://advisories.nats.io/CVE/secnote-2026-10.txtMitigation, Vendor Advisory
security-advisories@github.comhttps://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339Mitigation, Vendor Advisory
Impacted products
Vendor Product Version
linuxfoundation nats-server *
linuxfoundation nats-server *
To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "13EA156E-2759-4586-A22E-CDEAAD4D610C",
              "versionEndExcluding": "2.11.15",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "4E347CFB-C56D-4FD8-8DD8-3D34C08D7154",
              "versionEndExcluding": "2.12.6",
              "versionStartIncluding": "2.12.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "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."
    },
    {
      "lang": "es",
      "value": "NATS-Server es un servidor de alto rendimiento para NATS.io, un sistema de mensajer\u00eda nativo de la nube y del borde. Antes de las versiones 2.11.15 y 2.12.6, un cliente que puede conectarse al puerto leafnode puede bloquear el nats-server con un mensaje malformado espec\u00edfico pre-autenticaci\u00f3n. Las versiones 2.11.15 y 2.12.6 contienen una correcci\u00f3n. Como soluci\u00f3n alternativa, deshabilite el soporte de leafnode si no es necesario o restrinja las conexiones de red al puerto leafnode, si es factible sin comprometer el servicio ofrecido."
    }
  ],
  "id": "CVE-2026-33218",
  "lastModified": "2026-03-26T17:15:02.390",
  "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",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ],
      "url": "https://advisories.nats.io/CVE/secnote-2026-10.txt"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Mitigation",
        "Vendor Advisory"
      ],
      "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-vprv-35vv-q339"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-20"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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