Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-03-27 17:45

Modified

2026-09-08 08:34

Summary

NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing

Details

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, the NATS message header Nats-Request-Info: is supposed to be a guarantee of identity by the NATS server, but the stripping of this header from inbound messages was not fully effective. An attacker with valid credentials for any regular client interface could thus spoof their identity to services which rely upon this header. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "nats",
        "purl": "pkg:bitnami/nats"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.11.15"
            },
            {
              "introduced": "2.12.0"
            },
            {
              "fixed": "2.12.6"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33223"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:nats:nats_server:*:*:*:*:*:go:*:*"
    ],
    "severity": "Medium"
  },
  "details": "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, the NATS message header `Nats-Request-Info:` is supposed to be a guarantee of identity by the NATS server, but the stripping of this header from inbound messages was not fully effective. An attacker with valid credentials for any regular client interface could thus spoof their identity to services which rely upon this header. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.",
  "id": "BIT-nats-2026-33223",
  "modified": "2026-09-08T08:34:36.952Z",
  "published": "2026-03-27T17:45:21.527Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://advisories.nats.io/CVE/secnote-2026-09.txt"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-pwx7-fx9r-hr4h"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33223"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing"
}

CVE-2026-33223 (GCVE-0-2026-33223)

Vulnerability from cvelistv5 – Published: 2026-03-25 20:20 – Updated: 2026-03-26 17:51

Title

NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing

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, the NATS message header `Nats-Request-Info:` is supposed to be a guarantee of identity by the NATS server, but the stripping of this header from inbound messages was not fully effective. An attacker with valid credentials for any regular client interface could thus spoof their identity to services which rely upon this header. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available.

Severity

6.4 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-26 17:51 UTC

CWE

CWE-290 - Authentication Bypass by Spoofing

Assigner

GitHub_M mitre root Scorecard

References

2 references

URL	Tags
https://github.com/nats-io/nats-server/security/a…	x_refsource_CONFIRM
https://advisories.nats.io/CVE/secnote-2026-09.txt	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
nats-io	nats-server	Affected: < 2.11.15 Affected: >= 2.12.0-RC.1, < 2.12.6

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-33223",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-26T17:51:14.602692Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-26T17:51:23.590Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "nats-server",
          "vendor": "nats-io",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2.11.15"
            },
            {
              "status": "affected",
              "version": "\u003e= 2.12.0-RC.1, \u003c 2.12.6"
            }
          ]
        }
      ],
      "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, the NATS message header `Nats-Request-Info:` is supposed to be a guarantee of identity by the NATS server, but the stripping of this header from inbound messages was not fully effective. An attacker with valid credentials for any regular client interface could thus spoof their identity to services which rely upon this header. Versions 2.11.15 and 2.12.6 contain a fix. No known workarounds are available."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.4,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-290",
              "description": "CWE-290: Authentication Bypass by Spoofing",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-25T20:20:00.158Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/nats-io/nats-server/security/advisories/GHSA-pwx7-fx9r-hr4h",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/nats-io/nats-server/security/advisories/GHSA-pwx7-fx9r-hr4h"
        },
        {
          "name": "https://advisories.nats.io/CVE/secnote-2026-09.txt",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://advisories.nats.io/CVE/secnote-2026-09.txt"
        }
      ],
      "source": {
        "advisory": "GHSA-pwx7-fx9r-hr4h",
        "discovery": "UNKNOWN"
      },
      "title": "NATS Server: Incomplete Stripping of Nats-Request-Info Header Allows Identity Spoofing"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-33223",
    "datePublished": "2026-03-25T20:20:00.158Z",
    "dateReserved": "2026-03-17T23:23:58.315Z",
    "dateUpdated": "2026-03-26T17:51:23.590Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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Vulnerability from bitnami_vulndb

CVE-2026-33223 (GCVE-0-2026-33223)

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