Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-04-24 16:03

Modified

2026-04-28 09:12

Summary

MinIO has an Unauthenticated Object Write via Query-String Credential Signature Bypass in Unsigned-Trailer Uploads

Details

MinIO is a high-performance object storage system. Starting in 2023.05.18 and prior to 2026.04.11, an authentication bypass vulnerability in MinIO's STREAMING-UNSIGNED-PAYLOAD-TRAILER code path allows any user who knows a valid access key to write arbitrary objects to any bucket without knowing the secret key or providing a valid cryptographic signature. Any MinIO deployment is impacted. The attack requires only a valid access key (the well-known default minioadmin, or any key with WRITE permission on a bucket) and a target bucket name. PutObjectHandler and PutObjectPartHandler call newUnsignedV4ChunkedReader with a signature verification gate based solely on the presence of the Authorization header. Meanwhile, isPutActionAllowed extracts credentials from either the Authorization header or the X-Amz-Credential query parameter, and trusts whichever it finds. An attacker omits the Authorization header and supplies credentials exclusively via the query string. The signature gate evaluates to false, doesSignatureMatch is never called, and the request proceeds with the permissions of the impersonated access key. This affects PutObjectHandler (standard and tables/warehouse bucket paths) and PutObjectPartHandler (multipart uploads). Users of the open-source minio/minio project should upgrade to MinIO AIStor 2026.04.11 or later. If upgrading is not immediately possible, block unsigned-trailer requests at the load balancer. Reject any request containing X-Amz-Content-Sha256: STREAMING-UNSIGNED-PAYLOAD-TRAILER at the reverse proxy or WAF layer. Clients can use STREAMING-AWS4-HMAC-SHA256-PAYLOAD-TRAILER (the signed variant) instead. Alternatively, restrict WRITE permissions. Limit s3:PutObject grants to trusted principals. While this reduces the attack surface, it does not eliminate the vulnerability since any user with WRITE permission can exploit it with only their access key.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "minio",
        "purl": "pkg:bitnami/minio"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2023.05.18"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "type": "CVSS_V4"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-41145"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:minio:minio:*:*:*:*:*:*:*:*",
      "cpe:2.3:a:minio:minio:*:*:*:*:*:go:*:*"
    ],
    "severity": "High"
  },
  "details": "MinIO is a high-performance object storage system. Starting in 2023.05.18 and prior to 2026.04.11, an authentication bypass vulnerability in MinIO\u0027s `STREAMING-UNSIGNED-PAYLOAD-TRAILER` code path\nallows any user who knows a valid access key to write arbitrary objects to any bucket without knowing the secret key or providing a valid cryptographic signature. Any MinIO deployment is impacted. The attack requires only a valid access key (the well-known default `minioadmin`, or any key with WRITE permission on a bucket) and a target bucket name. `PutObjectHandler` and `PutObjectPartHandler` call `newUnsignedV4ChunkedReader` with a signature verification gate based solely on the presence of the `Authorization` header. Meanwhile, `isPutActionAllowed` extracts credentials from either the `Authorization` header or the\n`X-Amz-Credential` query parameter, and trusts whichever it finds. An attacker omits the `Authorization` header and supplies credentials exclusively via the query string. The signature gate evaluates to `false`, `doesSignatureMatch` is never called, and the request proceeds with the permissions of the impersonated access key. This affects `PutObjectHandler` (standard and tables/warehouse bucket paths) and `PutObjectPartHandler` (multipart uploads). Users of the open-source `minio/minio` project should upgrade to MinIO AIStor `2026.04.11` or later. If upgrading is not immediately possible, block unsigned-trailer requests at the load balancer. Reject any request containing `X-Amz-Content-Sha256: STREAMING-UNSIGNED-PAYLOAD-TRAILER` at the reverse proxy or WAF layer. Clients can use `STREAMING-AWS4-HMAC-SHA256-PAYLOAD-TRAILER` (the signed variant) instead. Alternatively, restrict WRITE permissions. Limit `s3:PutObject` grants to trusted principals. While this reduces the attack surface, it does not eliminate the vulnerability since any user with WRITE permission can exploit it with only their access key.",
  "id": "BIT-minio-2026-41145",
  "modified": "2026-04-28T09:12:07.790Z",
  "published": "2026-04-24T16:03:40.498Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/minio/minio/commit/76913a9fd5c6e5c2dbd4e8c7faf56ed9e9e24091"
    },
    {
      "type": "WEB",
      "url": "https://github.com/minio/minio/pull/16484"
    },
    {
      "type": "WEB",
      "url": "https://github.com/minio/minio/security/advisories/GHSA-hv4r-mvr4-25vw"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41145"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "MinIO has an Unauthenticated Object Write via Query-String Credential Signature Bypass in Unsigned-Trailer Uploads"
}

CVE-2026-41145 (GCVE-0-2026-41145)

Vulnerability from cvelistv5 – Published: 2026-04-22 00:54 – Updated: 2026-04-22 14:21

Title

MinIO has an Unauthenticated Object Write via Query-String Credential Signature Bypass in Unsigned-Trailer Uploads

Summary

MinIO is a high-performance object storage system. Starting in RELEASE.2023-05-18T00-05-36Z and prior to RELEASE.2026-04-11T03-20-12Z, an authentication bypass vulnerability in MinIO's `STREAMING-UNSIGNED-PAYLOAD-TRAILER` code path allows any user who knows a valid access key to write arbitrary objects to any bucket without knowing the secret key or providing a valid cryptographic signature. Any MinIO deployment is impacted. The attack requires only a valid access key (the well-known default `minioadmin`, or any key with WRITE permission on a bucket) and a target bucket name. `PutObjectHandler` and `PutObjectPartHandler` call `newUnsignedV4ChunkedReader` with a signature verification gate based solely on the presence of the `Authorization` header. Meanwhile, `isPutActionAllowed` extracts credentials from either the `Authorization` header or the `X-Amz-Credential` query parameter, and trusts whichever it finds. An attacker omits the `Authorization` header and supplies credentials exclusively via the query string. The signature gate evaluates to `false`, `doesSignatureMatch` is never called, and the request proceeds with the permissions of the impersonated access key. This affects `PutObjectHandler` (standard and tables/warehouse bucket paths) and `PutObjectPartHandler` (multipart uploads). Users of the open-source `minio/minio` project should upgrade to MinIO AIStor `RELEASE.2026-04-11T03-20-12Z` or later. If upgrading is not immediately possible, block unsigned-trailer requests at the load balancer. Reject any request containing `X-Amz-Content-Sha256: STREAMING-UNSIGNED-PAYLOAD-TRAILER` at the reverse proxy or WAF layer. Clients can use `STREAMING-AWS4-HMAC-SHA256-PAYLOAD-TRAILER` (the signed variant) instead. Alternatively, restrict WRITE permissions. Limit `s3:PutObject` grants to trusted principals. While this reduces the attack surface, it does not eliminate the vulnerability since any user with WRITE permission can exploit it with only their access key.

Severity ?

8.8 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N

CWE

CWE-287 - Improper Authentication

Assigner

GitHub_M

References

URL

Tags

	https://github.com/minio/minio/security/advisorie…	x_refsource_CONFIRM
	https://github.com/minio/minio/pull/16484	x_refsource_MISC
	https://github.com/minio/minio/commit/76913a9fd5c…	x_refsource_MISC

Impacted products

	Vendor	Product	Version
	minio	minio	Affected: >= RELEASE.2023-05-18T00-05-36Z, < RELEASE.2026-04-11T03-20-12Z

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-41145",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-22T14:21:29.040150Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-22T14:21:43.972Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "minio",
          "vendor": "minio",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= RELEASE.2023-05-18T00-05-36Z, \u003c RELEASE.2026-04-11T03-20-12Z"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "MinIO is a high-performance object storage system. Starting in RELEASE.2023-05-18T00-05-36Z and prior to RELEASE.2026-04-11T03-20-12Z, an authentication bypass vulnerability in MinIO\u0027s `STREAMING-UNSIGNED-PAYLOAD-TRAILER` code path\nallows any user who knows a valid access key to write arbitrary objects to any bucket without knowing the secret key or providing a valid cryptographic signature. Any MinIO deployment is impacted. The attack requires only a valid access key (the well-known default `minioadmin`, or any key with WRITE permission on a bucket) and a target bucket name. `PutObjectHandler` and `PutObjectPartHandler` call `newUnsignedV4ChunkedReader` with a signature verification gate based solely on the presence of the `Authorization` header. Meanwhile, `isPutActionAllowed` extracts credentials from either the `Authorization` header or the\n`X-Amz-Credential` query parameter, and trusts whichever it finds. An attacker omits the `Authorization` header and supplies credentials exclusively via the query string. The signature gate evaluates to `false`, `doesSignatureMatch` is never called, and the request proceeds with the permissions of the impersonated access key. This affects `PutObjectHandler` (standard and tables/warehouse bucket paths) and `PutObjectPartHandler` (multipart uploads). Users of the open-source `minio/minio` project should upgrade to MinIO AIStor `RELEASE.2026-04-11T03-20-12Z` or later. If upgrading is not immediately possible, block unsigned-trailer requests at the load balancer. Reject any request containing `X-Amz-Content-Sha256: STREAMING-UNSIGNED-PAYLOAD-TRAILER` at the reverse proxy or WAF layer. Clients can use `STREAMING-AWS4-HMAC-SHA256-PAYLOAD-TRAILER` (the signed variant) instead. Alternatively, restrict WRITE permissions. Limit `s3:PutObject` grants to trusted principals. While this reduces the attack surface, it does not eliminate the vulnerability since any user with WRITE permission can exploit it with only their access key."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.8,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-287",
              "description": "CWE-287: Improper Authentication",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-22T00:54:09.213Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/minio/minio/security/advisories/GHSA-hv4r-mvr4-25vw",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/minio/minio/security/advisories/GHSA-hv4r-mvr4-25vw"
        },
        {
          "name": "https://github.com/minio/minio/pull/16484",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/minio/minio/pull/16484"
        },
        {
          "name": "https://github.com/minio/minio/commit/76913a9fd5c6e5c2dbd4e8c7faf56ed9e9e24091",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/minio/minio/commit/76913a9fd5c6e5c2dbd4e8c7faf56ed9e9e24091"
        }
      ],
      "source": {
        "advisory": "GHSA-hv4r-mvr4-25vw",
        "discovery": "UNKNOWN"
      },
      "title": "MinIO has an Unauthenticated Object Write via Query-String Credential Signature Bypass in Unsigned-Trailer Uploads"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-41145",
    "datePublished": "2026-04-22T00:54:09.213Z",
    "dateReserved": "2026-04-17T12:59:15.739Z",
    "dateUpdated": "2026-04-22T14:21:43.972Z",
    "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.

Detection rules are retrieved from Rulezet.

Action not permitted

Vulnerability from bitnami_vulndb

CVE-2026-41145 (GCVE-0-2026-41145)

Tags

Sightings

Nomenclature