Vulnerability-Lookup

GHSA-RRMM-9V76-H3P4

Vulnerability from github – Published: 2026-05-14 16:22 – Updated: 2026-05-14 16:22

Summary

Portainer missing authorization on Docker plugin endpoints, which allows host RCE

Details

Summary

Portainer enforces Role-Based Access Control (RBAC) on top of the Docker API. The proxy layer routes incoming Docker API requests to per-resource handlers (containers, images, services, volumes, etc.) that apply authorization checks.

The Docker plugin management endpoints (/plugins/*) were not registered with a handler, so standard users with endpoint access could call privileged plugin operations — including installing and enabling plugins — directly against the underlying Docker daemon.

The vulnerability is exposed when a non-admin Portainer user (Standard User role, or any role granted endpoint-level access) has been given access to a Docker endpoint via Portainer RBAC. Administrators and users without Docker endpoint access are not affected.

A regular user with access to a Docker endpoint can:

Pull an arbitrary plugin from any registry via POST /plugins/pull.
Grant it the privileges it requests, including CAP_SYS_ADMIN and host-path mounts.
Enable the plugin via POST /plugins/{name}/enable, at which point Docker runs the plugin with root privileges on the host.

Docker plugins execute as root on the host and can request arbitrary host capabilities and mounts. Enabling a crafted plugin gives the user access to the host filesystem and equivalent to root on the Docker host.

Severity

Critical — CVSS 9.4 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

CWE-862 — Missing Authorization

Affected Versions

The vulnerability exists in every Portainer release where the Docker API proxy uses the prefix-allowlist routing model — /plugins has never been in the allowlist, and the fall-through path has never applied authorization.

Fixes are included in the next release of each supported branch:

Branch	First vulnerable	Fixed in
2.33.x (LTS)	2.33.0	2.33.8
2.39.x (LTS)	2.39.0	2.39.2
2.40.x (STS)	2.40.0	2.41.0

Portainer LTS branches receive fixes for 6 months plus a 3-month overlap after the next LTS ships. STS releases are supported only until the next STS ships — the 2.40.x STS line ends with the 2.41.0 release. All releases prior to 2.33.0 are end-of-life and will not receive a fix; users on EOL versions should upgrade to a supported LTS branch.

Workarounds

Administrators who cannot immediately upgrade can reduce exposure by temporarily revoking Docker endpoint access for non-admin users via Portainer RBAC until the patched release is deployed. This eliminates the attack surface without disruption for administrators. This does not replace the fix.

Affected Code

// api/http/proxy/factory/docker/transport.go (pre-fix)

var prefixProxyFuncMap = map[string]func(...){
    "build":      ...,
    "configs":    ...,
    "containers": ...,
    "images":     ...,
    "networks":   ...,
    "nodes":      ...,
    "secrets":    ...,
    "services":   ...,
    "swarm":      ...,
    "tasks":      ...,
    "v2":         ...,
    "volumes":    ...,
}

func (transport *Transport) ProxyDockerRequest(request *http.Request) (*http.Response, error) {
    // ...
    prefix := strings.Split(strings.TrimPrefix(unversionedPath, "/"), "/")[0]

    if proxyFunc := prefixProxyFuncMap[prefix]; proxyFunc != nil {
        return proxyFunc(transport, request, unversionedPath)  // authorized
    }

    return transport.executeDockerRequest(request)  // forwarded without authorization
}

/plugins is not in prefixProxyFuncMap, so requests to plugin endpoints fall through to executeDockerRequest and are forwarded to the Docker daemon without any Portainer-side authorization check.

Impact

An authenticated, non-admin Portainer user with access to any Docker-enabled endpoint can:

Install and enable arbitrary Docker plugins from any registry.
Execute plugin code with root privileges on the Docker host (including declaring CAP_SYS_ADMIN and host-path mounts).
Read and modify files on the host filesystem from a restricted account, overriding the administrator's security policy.

Timeline

2026-03-16: Reported via GitHub Security Advisory by ikkebr.
2026-04-20: Fix merged to develop, release/2.39, and release/2.33.
2026-04-29: 2.41.0 released.
2026-05-07: 2.39.2-LTS and 2.33.8-LTS released.

Credit

ikkebr — identified and reported the proxy allowlist bypass affecting the Docker plugin management endpoints.

Severity

9.4 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/portainer/portainer"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.33.0"
            },
            {
              "fixed": "2.33.8"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/portainer/portainer"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.39.0"
            },
            {
              "fixed": "2.39.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/portainer/portainer"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.40.0"
            },
            {
              "fixed": "2.41.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44848"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-862"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-14T16:22:50Z",
    "nvd_published_at": null,
    "severity": "CRITICAL"
  },
  "details": "## Summary\n\nPortainer enforces Role-Based Access Control (RBAC) on top of the Docker API. The proxy layer routes incoming Docker API requests to per-resource handlers (containers, images, services, volumes, etc.) that apply authorization checks.\n\nThe Docker plugin management endpoints (`/plugins/*`) were not registered with a handler, so standard users with endpoint access could call privileged plugin operations \u2014 including installing and enabling plugins \u2014 directly against the underlying Docker daemon.\n\nThe vulnerability is exposed when a non-admin Portainer user (Standard User role, or any role granted endpoint-level access) has been given access to a Docker endpoint via Portainer RBAC. Administrators and users without Docker endpoint access are not affected.\n\nA regular user with access to a Docker endpoint can:\n\n- Pull an arbitrary plugin from any registry via `POST /plugins/pull`.\n- Grant it the privileges it requests, including `CAP_SYS_ADMIN` and host-path mounts.\n- Enable the plugin via `POST /plugins/{name}/enable`, at which point Docker runs the plugin with root privileges on the host.\n\nDocker plugins execute as root on the host and can request arbitrary host capabilities and mounts. Enabling a crafted plugin gives the user access to the host filesystem and equivalent to root on the Docker host.\n\n## Severity\n\n**Critical** \u2014 CVSS 9.4\n`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H`\n\n**CWE-862** \u2014 Missing Authorization\n\n## Affected Versions\n\nThe vulnerability exists in every Portainer release where the Docker API proxy uses the prefix-allowlist routing model \u2014 `/plugins` has never been in the allowlist, and the fall-through path has never applied authorization.\n\nFixes are included in the next release of each supported branch:\n\n| Branch              | First vulnerable | Fixed in   |\n|---------------------|------------------|------------|\n| 2.33.x (LTS)        | 2.33.0           | **2.33.8** |\n| 2.39.x (LTS)        | 2.39.0           | **2.39.2** |\n| 2.40.x (STS)        | 2.40.0           | **2.41.0** |\n\nPortainer LTS branches receive fixes for 6 months plus a 3-month overlap after the next LTS ships. STS releases are supported only until the next STS ships \u2014 the 2.40.x STS line ends with the 2.41.0 release. All releases **prior to 2.33.0 are end-of-life** and will not receive a fix; users on EOL versions should upgrade to a supported LTS branch.\n\n## Workarounds\n\nAdministrators who cannot immediately upgrade can reduce exposure by temporarily **revoking Docker endpoint access for non-admin users** via Portainer RBAC until the patched release is deployed. This eliminates the attack surface without disruption for administrators. This does not replace the fix.\n\n## Affected Code\n\n```go\n// api/http/proxy/factory/docker/transport.go (pre-fix)\n\nvar prefixProxyFuncMap = map[string]func(...){\n    \"build\":      ...,\n    \"configs\":    ...,\n    \"containers\": ...,\n    \"images\":     ...,\n    \"networks\":   ...,\n    \"nodes\":      ...,\n    \"secrets\":    ...,\n    \"services\":   ...,\n    \"swarm\":      ...,\n    \"tasks\":      ...,\n    \"v2\":         ...,\n    \"volumes\":    ...,\n}\n\nfunc (transport *Transport) ProxyDockerRequest(request *http.Request) (*http.Response, error) {\n    // ...\n    prefix := strings.Split(strings.TrimPrefix(unversionedPath, \"/\"), \"/\")[0]\n\n    if proxyFunc := prefixProxyFuncMap[prefix]; proxyFunc != nil {\n        return proxyFunc(transport, request, unversionedPath)  // authorized\n    }\n\n    return transport.executeDockerRequest(request)  // forwarded without authorization\n}\n```\n\n`/plugins` is not in `prefixProxyFuncMap`, so requests to plugin endpoints fall through to `executeDockerRequest` and are forwarded to the Docker daemon without any Portainer-side authorization check.\n\n\n## Impact\n\nAn authenticated, non-admin Portainer user with access to any Docker-enabled endpoint can:\n\n- Install and enable arbitrary Docker plugins from any registry.\n- Execute plugin code with root privileges on the Docker host (including declaring `CAP_SYS_ADMIN` and host-path mounts).\n- Read and modify files on the host filesystem from a restricted account, overriding the administrator\u0027s security policy.\n\n## Timeline\n\n- 2026-03-16: Reported via GitHub Security Advisory by **ikkebr**.\n- 2026-04-20: Fix merged to `develop`, `release/2.39`, and `release/2.33`.\n- 2026-04-29: 2.41.0 released.\n- 2026-05-07: 2.39.2-LTS and 2.33.8-LTS released.\n\n## Credit\n\n- **ikkebr** \u2014 identified and reported the proxy allowlist bypass affecting the Docker plugin management endpoints.",
  "id": "GHSA-rrmm-9v76-h3p4",
  "modified": "2026-05-14T16:22:50Z",
  "published": "2026-05-14T16:22:50Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/portainer/portainer/security/advisories/GHSA-rrmm-9v76-h3p4"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/portainer/portainer"
    },
    {
      "type": "WEB",
      "url": "https://github.com/portainer/portainer/releases/tag/2.33.8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/portainer/portainer/releases/tag/2.39.2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/portainer/portainer/releases/tag/2.41.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Portainer missing authorization on Docker plugin endpoints, which allows host RCE"
}

CVE-2026-44848 (GCVE-0-2026-44848)

Vulnerability from cvelistv5 – Published: 2026-05-28 21:08 – Updated: 2026-06-01 18:59

Title

Portainer: Missing authorization on Docker plugin endpoints allows host RCE

Summary

Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33.8, 2.39.2, and 2.41.0, The Docker plugin management endpoints (/plugins/*) were not registered with a handler, so standard users with endpoint access could call privileged plugin operations — including installing and enabling plugins — directly against the underlying Docker daemon. The vulnerability is exposed when a non-admin Portainer user (Standard User role, or any role granted endpoint-level access) has been given access to a Docker endpoint via Portainer RBAC. This vulnerability is fixed in 2.33.8, 2.39.2, and 2.41.0.

Severity

9.4 (Critical)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-862 - Missing Authorization

Assigner

GitHub_M

References

1 reference

URL	Tags
https://github.com/portainer/portainer/security/a…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version
portainer	portainer	Affected: >= 2.33.0, < 2.33.8 Affected: >= 2.39.0, < 2.39.2 Affected: >= 2.40.0, < 2.41.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-44848",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-01T18:58:48.296970Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-01T18:59:07.188Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/portainer/portainer/security/advisories/GHSA-rrmm-9v76-h3p4"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "portainer",
          "vendor": "portainer",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 2.33.0, \u003c 2.33.8"
            },
            {
              "status": "affected",
              "version": "\u003e= 2.39.0, \u003c 2.39.2"
            },
            {
              "status": "affected",
              "version": "\u003e= 2.40.0, \u003c 2.41.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33.8, 2.39.2, and 2.41.0, The Docker plugin management endpoints (/plugins/*) were not registered with a handler, so standard users with endpoint access could call privileged plugin operations \u2014 including installing and enabling plugins \u2014 directly against the underlying Docker daemon. The vulnerability is exposed when a non-admin Portainer user (Standard User role, or any role granted endpoint-level access) has been given access to a Docker endpoint via Portainer RBAC. This vulnerability is fixed in 2.33.8, 2.39.2, and 2.41.0."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.4,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "LOW",
            "subAvailabilityImpact": "HIGH",
            "subConfidentialityImpact": "HIGH",
            "subIntegrityImpact": "HIGH",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-05-28T21:08:17.057Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/portainer/portainer/security/advisories/GHSA-rrmm-9v76-h3p4",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/portainer/portainer/security/advisories/GHSA-rrmm-9v76-h3p4"
        }
      ],
      "source": {
        "advisory": "GHSA-rrmm-9v76-h3p4",
        "discovery": "UNKNOWN"
      },
      "title": "Portainer: Missing authorization on Docker plugin endpoints allows host RCE"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-44848",
    "datePublished": "2026-05-28T21:08:17.057Z",
    "dateReserved": "2026-05-07T21:21:48.353Z",
    "dateUpdated": "2026-06-01T18:59:07.188Z",
    "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

GHSA-RRMM-9V76-H3P4

Summary

Severity

Affected Versions

Workarounds

Affected Code

Impact

Timeline

Credit

CVE-2026-44848 (GCVE-0-2026-44848)

Tags

Sightings

Nomenclature