Vulnerability-Lookup

GHSA-WMGG-3P4H-48X7

Vulnerability from github – Published: 2026-06-30 18:18 – Updated: 2026-06-30 18:18

Summary

Fission Environment CRD PodSpec Injection Leading to Node Escape and Cluster Takeover

Details

Summary

A stronger framing of the same root cause as GHSA-gx55-f84r-v3r7: the Environment.spec.runtime.podSpec / spec.builder.podSpec passthrough lacked validation, and MergePodSpec propagated dangerous fields into the generated pods.

Details

Three independent flaws compounded:

Validate gap. pkg/apis/core/v1/validation.go::Environment.Validate checked only container naming conventions, never hostPID/hostIPC/hostNetwork/hostPath/privileged.
UPDATE bypass. The pkg/webhook/environment.go kubebuilder marker registered verbs=create only. A tenant could kubectl apply a clean Environment and then kubectl patch in the dangerous fields — the webhook was never called.
Merge propagation. pkg/executor/util/merge.go::MergePodSpec unconditionally forwarded HostPID, HostIPC, HostNetwork, Volumes (including hostPath), SecurityContext, and ServiceAccountName into the Deployments generated by poolmgr / newdeploy / buildermgr.

A kubectl apply plus a follow-up kubectl patch caused poolmgr to schedule a privileged pod with a host-root mount within roughly 20 seconds. From that pod the cluster CA private key was readable, allowing the attacker to sign arbitrary kubelet certificates and achieve full cluster takeover.

Impact

environments.fission.io create/update RBAC is escalated to node escape and, via the readable cluster CA key, full cluster takeover.

Fix

Fixed in #3391 (with the companion buildermgr SA-token fix in #3390) and released in v1.24.0. Each enumerated flaw is addressed:

Validate — ValidatePodSpecSafety is called from Environment.Validate for both Runtime.PodSpec and Builder.PodSpec.
UPDATE bypass — the webhook marker is extended to verbs=create;update; chart and envtest manifests are aligned.
Merge propagation — host namespaces, ServiceAccountName, and hostPath volumes are stripped at the merge layer; per-container privileged/allowPrivilegeEscalation and dangerous capabilities are sanitized.

See GHSA-gx55-f84r-v3r7 for the detailed fix — both advisories close to the same commit.

Duplicate handling

This advisory and GHSA-gx55-f84r-v3r7 were reported separately but close to the same code fix. Both are published to acknowledge each reporter's contribution and to keep the public CVE record clear about the multi-layer nature of the issue.

Severity

9.9 (Critical)


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

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JSON

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.23.0"
      },
      "package": {
        "ecosystem": "Go",
        "name": "github.com/fission/fission"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.24.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-50545"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-269",
      "CWE-284",
      "CWE-693"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-30T18:18:05Z",
    "nvd_published_at": "2026-06-10T18:17:12Z",
    "severity": "CRITICAL"
  },
  "details": "### Summary\n\nA stronger framing of the same root cause as GHSA-gx55-f84r-v3r7: the `Environment.spec.runtime.podSpec` / `spec.builder.podSpec` passthrough lacked validation, and `MergePodSpec` propagated dangerous fields into the generated pods.\n\n### Details\n\nThree independent flaws compounded:\n\n1. **Validate gap.** `pkg/apis/core/v1/validation.go::Environment.Validate` checked only container naming conventions, never `hostPID`/`hostIPC`/`hostNetwork`/`hostPath`/`privileged`.\n2. **UPDATE bypass.** The `pkg/webhook/environment.go` kubebuilder marker registered `verbs=create` only. A tenant could `kubectl apply` a clean Environment and then `kubectl patch` in the dangerous fields \u2014 the webhook was never called.\n3. **Merge propagation.** `pkg/executor/util/merge.go::MergePodSpec` unconditionally forwarded `HostPID`, `HostIPC`, `HostNetwork`, `Volumes` (including hostPath), `SecurityContext`, and `ServiceAccountName` into the Deployments\ngenerated by poolmgr / newdeploy / buildermgr.\n\nA `kubectl apply` plus a follow-up `kubectl patch` caused poolmgr to schedule a privileged pod with a host-root mount within roughly 20 seconds. From that pod the cluster CA private key was readable, allowing the attacker to sign\narbitrary kubelet certificates and achieve full cluster takeover.\n\n### Impact\n\n`environments.fission.io` create/update RBAC is escalated to node escape and, via the readable cluster CA key, full cluster takeover.\n\n### Fix\n\nFixed in [#3391](https://github.com/fission/fission/pull/3391) (with the companion buildermgr SA-token fix in [#3390](https://github.com/fission/fission/pull/3390)) and released in\n[v1.24.0](https://github.com/fission/fission/releases/tag/v1.24.0). Each enumerated flaw is addressed:\n\n1. **Validate** \u2014 `ValidatePodSpecSafety` is called from `Environment.Validate` for both `Runtime.PodSpec` and `Builder.PodSpec`.\n2. **UPDATE bypass** \u2014 the webhook marker is extended to `verbs=create;update`; chart and envtest manifests are aligned.\n3. **Merge propagation** \u2014 host namespaces, `ServiceAccountName`, and hostPath volumes are stripped at the merge layer; per-container `privileged`/`allowPrivilegeEscalation` and dangerous capabilities are sanitized.\n\nSee GHSA-gx55-f84r-v3r7 for the detailed fix \u2014 both advisories close to the same commit.\n\n### Duplicate handling\n\nThis advisory and GHSA-gx55-f84r-v3r7 were reported separately but close to the same code fix. Both are published to acknowledge each reporter\u0027s contribution and to keep the public CVE record clear about the multi-layer nature of the\nissue.",
  "id": "GHSA-wmgg-3p4h-48x7",
  "modified": "2026-06-30T18:18:05Z",
  "published": "2026-06-30T18:18:05Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/security/advisories/GHSA-wmgg-3p4h-48x7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-50545"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/pull/3390"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/pull/3391"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/commit/8fa799417c77ce8a0189d9858bfe11ece29b84a6"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/commit/e484df8460bb4e8026e24210120602aa7f181f64"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/fission/fission"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/releases/tag/v1.24.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Fission Environment CRD PodSpec Injection Leading to Node Escape and Cluster Takeover"
}

CVE-2026-50545 (GCVE-0-2026-50545)

Vulnerability from cvelistv5 – Published: 2026-06-10 17:26 – Updated: 2026-06-12 03:55

Title

Fission Environment CRD PodSpec Injection Leading to Node Escape and Cluster Takeover

Summary

Fission is an open-source, Kubernetes-native serverless framework that simplifies the deployment of functions and applications on Kubernetes. Prior to version 1.24.0, the Environment.spec.runtime.podSpec / spec.builder.podSpec passthrough lacked validation, and MergePodSpec propagated dangerous fields into the generated pods. This issue has been patched in version 1.24.0.

Severity

9.9 (Critical)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator (v2.0.3)

CWE

CWE-269 - Improper Privilege Management
CWE-284 - Improper Access Control
CWE-693 - Protection Mechanism Failure

Assigner

GitHub_M

References

4 references

URL	Tags
https://github.com/fission/fission/security/advis…	x_refsource_CONFIRM
https://github.com/fission/fission/pull/3390	x_refsource_MISC
https://github.com/fission/fission/pull/3391	x_refsource_MISC
https://github.com/fission/fission/releases/tag/v1.24.0	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
fission	fission	Affected: < 1.24.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-50545",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-11T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-12T03:55:19.795Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "fission",
          "vendor": "fission",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.24.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Fission is an open-source, Kubernetes-native serverless framework that simplifies the deployment of functions and applications on Kubernetes. Prior to version 1.24.0, the Environment.spec.runtime.podSpec / spec.builder.podSpec passthrough lacked validation, and MergePodSpec propagated dangerous fields into the generated pods. This issue has been patched in version 1.24.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.9,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-269",
              "description": "CWE-269: Improper Privilege Management",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-284",
              "description": "CWE-284: Improper Access Control",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-693",
              "description": "CWE-693: Protection Mechanism Failure",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-10T17:26:20.647Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/fission/fission/security/advisories/GHSA-wmgg-3p4h-48x7",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/fission/fission/security/advisories/GHSA-wmgg-3p4h-48x7"
        },
        {
          "name": "https://github.com/fission/fission/pull/3390",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/fission/fission/pull/3390"
        },
        {
          "name": "https://github.com/fission/fission/pull/3391",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/fission/fission/pull/3391"
        },
        {
          "name": "https://github.com/fission/fission/releases/tag/v1.24.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/fission/fission/releases/tag/v1.24.0"
        }
      ],
      "source": {
        "advisory": "GHSA-wmgg-3p4h-48x7",
        "discovery": "UNKNOWN"
      },
      "title": "Fission Environment CRD PodSpec Injection Leading to Node Escape and Cluster Takeover"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-50545",
    "datePublished": "2026-06-10T17:26:20.647Z",
    "dateReserved": "2026-06-04T20:37:18.653Z",
    "dateUpdated": "2026-06-12T03:55:19.795Z",
    "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-WMGG-3P4H-48X7

Summary

Details

Impact

Fix

Duplicate handling

CVE-2026-50545 (GCVE-0-2026-50545)

Tags

Sightings

Nomenclature