FKIE_CVE-2026-27889

Vulnerability from fkie_nvd - Published: 2026-03-25 20:16 - Updated: 2026-09-09 13:19
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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. Starting in version 2.2.0 and prior to versions 2.11.14 and 2.12.5, a missing sanity check on a WebSockets frame could trigger a server panic in the nats-server. This happens before authentication, and so is exposed to anyone who can connect to the websockets port. Versions 2.11.14 and 2.12.5 contains a fix. A workaround is available. The vulnerability only affects deployments which use WebSockets and which expose the network port to untrusted end-points. If one is able to do so, a defense in depth of restricting either of these will mitigate the attack.
References
security-advisories@github.comhttps://advisories.nats.io/CVE/secnote-2026-03.txtMitigation, Vendor Advisory
security-advisories@github.comhttps://github.com/nats-io/nats-server/security/advisories/GHSA-pq2q-rcw4-3hr6Mitigation, Vendor Advisory
0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:21769
0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:22347
0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/errata/RHSA-2026:23345
0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://access.redhat.com/security/cve/CVE-2026-27889
0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://bugzilla.redhat.com/show_bug.cgi?id=2451447
0b0ca135-0b70-47e7-9f44-1890c2a1c46chttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27889.json
Impacted products
Vendor Product Version
linuxfoundation nats-server *
linuxfoundation nats-server *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "nats-server",
          "vendor": "nats-io",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2.2.0, \u003c 2.11.14"
            },
            {
              "status": "affected",
              "version": "\u003e= 2.12.0, \u003c 2.12.5"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    },
    {
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          "cpes": [
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          ],
          "defaultStatus": "affected",
          "packageName": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9",
          "product": "Multicluster Global Hub 1.4.5",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "1779579439",
              "versionType": "rpm"
            }
          ]
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        {
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          "cpes": [
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          ],
          "defaultStatus": "affected",
          "packageName": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9",
          "product": "Multicluster Global Hub 1.6.5",
          "vendor": "Red Hat",
          "versions": [
            {
              "lessThan": "*",
              "status": "unaffected",
              "version": "1780167118",
              "versionType": "rpm"
            }
          ]
        },
        {
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          "cpes": [
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          ],
          "defaultStatus": "affected",
          "packageName": "multicluster-globalhub/multicluster-globalhub-grafana-rhel9",
          "product": "Red Hat multicluster global hub 1.5.3",
          "vendor": "Red Hat",
          "versions": [
            {
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              "status": "unaffected",
              "version": "1778867753",
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          ]
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        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
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          ],
          "defaultStatus": "unaffected",
          "packageName": "openshift4/oc-mirror-plugin-rhel9",
          "product": "Red Hat OpenShift Container Platform 4",
          "vendor": "Red Hat"
        }
      ],
      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "6681EAC6-5A1D-4F3A-926C-F7BEB21791AA",
              "versionEndExcluding": "2.11.14",
              "versionStartIncluding": "2.2.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "B141DA72-3502-4746-A246-EE1087C993F4",
              "versionEndExcluding": "2.12.5",
              "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. Starting in version 2.2.0 and prior to versions 2.11.14 and 2.12.5, a missing sanity check on a WebSockets frame could trigger a server panic in the nats-server.  This happens before authentication, and so is exposed to anyone who can connect to the websockets port. Versions 2.11.14 and 2.12.5 contains a fix. A workaround is available. The vulnerability only affects deployments which use WebSockets and which expose the network port to untrusted end-points. If one is able to do so, a defense in depth of restricting either of these will mitigate the attack."
    },
    {
      "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. A partir de la versi\u00f3n 2.2.0 y antes de las versiones 2.11.14 y 2.12.5, una comprobaci\u00f3n de cordura faltante en un marco de WebSockets podr\u00eda desencadenar un p\u00e1nico del servidor en el nats-server. Esto ocurre antes de la autenticaci\u00f3n, y por lo tanto est\u00e1 expuesto a cualquiera que pueda conectarse al puerto de websockets. Las versiones 2.11.14 y 2.12.5 contienen una correcci\u00f3n. Una soluci\u00f3n alternativa est\u00e1 disponible. La vulnerabilidad solo afecta a las implementaciones que usan WebSockets y que exponen el puerto de red a puntos finales no confiables. Si uno es capaz de hacerlo, una defensa en profundidad de restringir cualquiera de estos mitigar\u00e1 el ataque."
    }
  ],
  "id": "CVE-2026-27889",
  "lastModified": "2026-09-09T13:19:10.343",
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        "cvssData": {
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          "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"
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        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
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          "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",
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        "ssvcData": {
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          "options": [
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              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
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          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-03-25T20:06:22.827675Z",
          "version": "2.0.3"
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  "published": "2026-03-25T20:16:27.210",
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  "vulnStatus": "Modified",
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  ]
}



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