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GHSA-GC3J-79F2-7VVW

Vulnerability from github – Published: 2026-06-30 18:16 – Updated: 2026-06-30 18:16

Summary

Fission: Cross-namespace event leakage via KubernetesWatchTrigger allows persistent tenant surveillance

Details

Summary

A low-privilege developer who could create a KubernetesWatchTrigger (KWT) in their own namespace was able to establish a persistent surveillance channel over any other namespace.

Details

Two independent flaws compounded:

pkg/kubewatcher/kubewatcher.go::createKubernetesWatch used w.Spec.Namespace (user-controlled) directly as the Watch target without checking it against w.Namespace (the KWT's own namespace). kubewatcher established the Watch using its cluster-scoped service account and serialized every Pod/Service/Job change event as full JSON over HTTP POST to the attacker's function.
The validating webhook (pkg/webhook/kuberneteswatchtrigger.go) registered verbs=create only, so update/patch requests bypassed validation entirely.

A separate leak: an empty spec.namespace resolved to all namespaces via the controller's default, letting an attacker omit the field to surveil the entire cluster.

Impact

A tenant with kuberneteswatchtriggers.fission.io/create could continuously receive full event payloads for Pods, Services, and Jobs in any namespace — a persistent cross-tenant surveillance channel requiring no additional privileges.

Fix

Fixed in #3379 and released in v1.24.0.

The validating webhook marker is extended to verbs=create;update.
Validate rejects KubernetesWatchTrigger.spec.namespace != metadata.namespace.
A controller guard in createKubernetesWatch rejects cross-namespace targets that bypass admission and coerces an empty Spec.Namespace to the trigger's own namespace.

Behavioural change

KubernetesWatchTriggers with an unset spec.namespace now watch only their own namespace instead of all namespaces. Anyone relying on the previous all-namespaces behaviour must create a separate KWT per namespace.

Severity

7.7 (High)


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

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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-2026-49822"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-284",
      "CWE-862"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-30T18:16:03Z",
    "nvd_published_at": "2026-06-10T18:17:10Z",
    "severity": "HIGH"
  },
  "details": "### Summary\n\nA low-privilege developer who could create a `KubernetesWatchTrigger` (KWT) in their own namespace was able to establish a persistent surveillance channel over any other namespace.\n\n### Details\n\nTwo independent flaws compounded:\n\n1. `pkg/kubewatcher/kubewatcher.go::createKubernetesWatch` used `w.Spec.Namespace` (user-controlled) directly as the Watch target without checking it against `w.Namespace` (the KWT\u0027s own namespace). `kubewatcher` established the Watch\nusing its cluster-scoped service account and serialized every Pod/Service/Job change event as full JSON over HTTP POST to the attacker\u0027s function.\n2. The validating webhook (`pkg/webhook/kuberneteswatchtrigger.go`) registered `verbs=create` only, so `update`/`patch` requests bypassed validation entirely.\n\nA separate leak: an empty `spec.namespace` resolved to **all namespaces** via the controller\u0027s default, letting an attacker omit the field to surveil the entire cluster.\n\n### Impact\n\nA tenant with `kuberneteswatchtriggers.fission.io/create` could continuously receive full event payloads for Pods, Services, and Jobs in any namespace \u2014 a persistent cross-tenant surveillance channel requiring no additional privileges.\n\n### Fix\n\nFixed in [#3379](https://github.com/fission/fission/pull/3379) and released in [v1.24.0](https://github.com/fission/fission/releases/tag/v1.24.0).\n\n- The validating webhook marker is extended to `verbs=create;update`.\n- `Validate` rejects `KubernetesWatchTrigger.spec.namespace != metadata.namespace`.\n- A controller guard in `createKubernetesWatch` rejects cross-namespace targets that bypass admission and coerces an empty `Spec.Namespace` to the trigger\u0027s own namespace.\n\n### Behavioural change\n\nKubernetesWatchTriggers with an unset `spec.namespace` now watch only their own namespace instead of all namespaces. Anyone relying on the previous all-namespaces behaviour must create a separate KWT per namespace.",
  "id": "GHSA-gc3j-79f2-7vvw",
  "modified": "2026-06-30T18:16:03Z",
  "published": "2026-06-30T18:16:03Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/security/advisories/GHSA-gc3j-79f2-7vvw"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-49822"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/pull/3379"
    },
    {
      "type": "WEB",
      "url": "https://github.com/fission/fission/commit/e2b92663499f4dc3a1e2d38178f39c3c65e0134a"
    },
    {
      "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:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Fission: Cross-namespace event leakage via KubernetesWatchTrigger allows persistent tenant surveillance"
}

CVE-2026-49822 (GCVE-0-2026-49822)

Vulnerability from cvelistv5 – Published: 2026-06-10 17:22 – Updated: 2026-06-10 18:43

Title

Fission: Cross-namespace event leakage via KubernetesWatchTrigger allows persistent tenant surveillance

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, a low-privilege developer who could create a KubernetesWatchTrigger (KWT) in their own namespace was able to establish a persistent surveillance channel over any other namespace. This issue has been patched in version 1.24.0.

Severity

7.7 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-284 - Improper Access Control
CWE-862 - Missing Authorization

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/fission/fission/security/advis…	x_refsource_CONFIRM
https://github.com/fission/fission/pull/3379	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-2026-49822",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-10T18:43:36.845307Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-10T18:43:43.806Z",
          "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": [
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 7.7,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
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          "descriptions": [
            {
              "cweId": "CWE-284",
              "description": "CWE-284: Improper Access Control",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-10T17:22:08.007Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/fission/fission/security/advisories/GHSA-gc3j-79f2-7vvw",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/fission/fission/security/advisories/GHSA-gc3j-79f2-7vvw"
        },
        {
          "name": "https://github.com/fission/fission/pull/3379",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/fission/fission/pull/3379"
        },
        {
          "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-gc3j-79f2-7vvw",
        "discovery": "UNKNOWN"
      },
      "title": "Fission: Cross-namespace event leakage via KubernetesWatchTrigger allows persistent tenant surveillance"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-49822",
    "datePublished": "2026-06-10T17:22:08.007Z",
    "dateReserved": "2026-06-01T18:50:36.055Z",
    "dateUpdated": "2026-06-10T18:43:43.806Z",
    "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-GC3J-79F2-7VVW

Summary

Details

Impact

Fix

Behavioural change

CVE-2026-49822 (GCVE-0-2026-49822)

Tags

Sightings

Nomenclature