CVE-2026-5427 (GCVE-0-2026-5427)

Vulnerability from cvelistv5 – Published: 2026-04-17 03:36 – Updated: 2026-04-17 18:48
VLAI
Title
Kubio AI Page Builder <= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes
Summary
The Kubio plugin for WordPress is vulnerable to Arbitrary File Upload in versions up to and including 2.7.2. This is due to insufficient capability checks in the kubio_rest_pre_insert_import_assets() function, which is hooked to the rest_pre_insert_{post_type} filter for posts, pages, templates, and template parts. When a post is created or updated via the REST API, Kubio parses block attributes looking for URLs in the 'kubio' attribute namespace and automatically imports them via importRemoteFile() without verifying the user has the upload_files capability. This makes it possible for authenticated attackers with Contributor-level access and above to bypass WordPress's normal media upload restrictions and upload files fetched from external URLs to the media library, creating attachment posts in the database.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-17 18:48 UTC
CWE
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2430 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
extendthemes Kubio AI Page Builder Affected: 0 , ≤ 2.7.2 (semver)
guessed Create a notification for this product.
Credits
SeungRyeol Baek
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-5427",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-17T18:48:48.792992Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-17T18:48:57.774Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Kubio AI Page Builder",
          "vendor": "extendthemes",
          "versions": [
            {
              "lessThanOrEqual": "2.7.2",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "SeungRyeol Baek"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Kubio plugin for WordPress is vulnerable to Arbitrary File Upload in versions up to and including 2.7.2. This is due to insufficient capability checks in the kubio_rest_pre_insert_import_assets() function, which is hooked to the rest_pre_insert_{post_type} filter for posts, pages, templates, and template parts. When a post is created or updated via the REST API, Kubio parses block attributes looking for URLs in the \u0027kubio\u0027 attribute namespace and automatically imports them via importRemoteFile() without verifying the user has the upload_files capability. This makes it possible for authenticated attackers with Contributor-level access and above to bypass WordPress\u0027s normal media upload restrictions and upload files fetched from external URLs to the media library, creating attachment posts in the database."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862 Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-04-17T03:36:44.993Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d8096f3c-e1a9-424f-af10-3e80212db985?source=cve"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/src/Core/Importer.php#L546"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/src/Core/Importer.php#L546"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/importer/importer-filters/kubio-blocks.php#L20"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/importer/importer-filters/kubio-blocks.php#L20"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/filters/post-insert.php#L17"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/filters/post-insert.php#L17"
        },
        {
          "url": "https://plugins.trac.wordpress.org/changeset/3506647/kubio/trunk/lib/src/Core/Importer.php"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-04-02T14:40:37.000Z",
          "value": "Vendor Notified"
        },
        {
          "lang": "en",
          "time": "2026-04-16T15:06:55.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "Kubio AI Page Builder \u003c= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
    "assignerShortName": "Wordfence",
    "cveId": "CVE-2026-5427",
    "datePublished": "2026-04-17T03:36:44.993Z",
    "dateReserved": "2026-04-02T14:24:35.903Z",
    "dateUpdated": "2026-04-17T18:48:57.774Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-5427",
      "date": "2026-11-11",
      "epss": "0.00536",
      "percentile": "0.45634"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Kubio AI Page Builder",
                "vendor": "extendthemes",
                "versions": [
                  {
                    "lessThanOrEqual": "2.7.2",
                    "status": "affected",
                    "version": "0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "security@wordfence.com"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "The Kubio plugin for WordPress is vulnerable to Arbitrary File Upload in versions up to and including 2.7.2. This is due to insufficient capability checks in the kubio_rest_pre_insert_import_assets() function, which is hooked to the rest_pre_insert_{post_type} filter for posts, pages, templates, and template parts. When a post is created or updated via the REST API, Kubio parses block attributes looking for URLs in the \u0027kubio\u0027 attribute namespace and automatically imports them via importRemoteFile() without verifying the user has the upload_files capability. This makes it possible for authenticated attackers with Contributor-level access and above to bypass WordPress\u0027s normal media upload restrictions and upload files fetched from external URLs to the media library, creating attachment posts in the database."
          }
        ],
        "id": "CVE-2026-5427",
        "lastModified": "2026-06-17T10:59:00.787",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 5.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "LOW",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 1.4,
              "source": "security@wordfence.com",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-5427",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "yes"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-17T18:48:48.792992Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-04-17T05:16:18.973",
        "references": [
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/filters/post-insert.php#L17"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/importer/importer-filters/kubio-blocks.php#L20"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/src/Core/Importer.php#L546"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/filters/post-insert.php#L17"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/importer/importer-filters/kubio-blocks.php#L20"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/src/Core/Importer.php#L546"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://plugins.trac.wordpress.org/changeset/3506647/kubio/trunk/lib/src/Core/Importer.php"
          },
          {
            "source": "security@wordfence.com",
            "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d8096f3c-e1a9-424f-af10-3e80212db985?source=cve"
          }
        ],
        "sourceIdentifier": "security@wordfence.com",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-862"
              }
            ],
            "source": "security@wordfence.com",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "current_release_date": "2026-06-05T19:35:10+00:00",
      "cve": "CVE-2026-5427",
      "id": "CVE-2026-5427",
      "initial_release_date": "2026-01-01T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Kubio AI Page Builder \u003c= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5427.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-5427",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-04-17T18:48:48.792992Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-04-17T18:48:53.490Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "Kubio AI Page Builder",
              "vendor": "extendthemes",
              "versions": [
                {
                  "lessThanOrEqual": "2.7.2",
                  "status": "affected",
                  "version": "0",
                  "versionType": "semver"
                }
              ]
            }
          ],
          "credits": [
            {
              "lang": "en",
              "type": "finder",
              "value": "SeungRyeol Baek"
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "The Kubio plugin for WordPress is vulnerable to Arbitrary File Upload in versions up to and including 2.7.2. This is due to insufficient capability checks in the kubio_rest_pre_insert_import_assets() function, which is hooked to the rest_pre_insert_{post_type} filter for posts, pages, templates, and template parts. When a post is created or updated via the REST API, Kubio parses block attributes looking for URLs in the \u0027kubio\u0027 attribute namespace and automatically imports them via importRemoteFile() without verifying the user has the upload_files capability. This makes it possible for authenticated attackers with Contributor-level access and above to bypass WordPress\u0027s normal media upload restrictions and upload files fetched from external URLs to the media library, creating attachment posts in the database."
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "baseScore": 5.3,
                "baseSeverity": "MEDIUM",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
                "version": "3.1"
              }
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-862",
                  "description": "CWE-862 Missing Authorization",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-04-17T03:36:44.993Z",
            "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
            "shortName": "Wordfence"
          },
          "references": [
            {
              "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d8096f3c-e1a9-424f-af10-3e80212db985?source=cve"
            },
            {
              "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/src/Core/Importer.php#L546"
            },
            {
              "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/src/Core/Importer.php#L546"
            },
            {
              "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/importer/importer-filters/kubio-blocks.php#L20"
            },
            {
              "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/importer/importer-filters/kubio-blocks.php#L20"
            },
            {
              "url": "https://plugins.trac.wordpress.org/browser/kubio/trunk/lib/filters/post-insert.php#L17"
            },
            {
              "url": "https://plugins.trac.wordpress.org/browser/kubio/tags/2.7.1/lib/filters/post-insert.php#L17"
            },
            {
              "url": "https://plugins.trac.wordpress.org/changeset/3506647/kubio/trunk/lib/src/Core/Importer.php"
            }
          ],
          "timeline": [
            {
              "lang": "en",
              "time": "2026-04-02T14:40:37.000Z",
              "value": "Vendor Notified"
            },
            {
              "lang": "en",
              "time": "2026-04-16T15:06:55.000Z",
              "value": "Disclosed"
            }
          ],
          "title": "Kubio AI Page Builder \u003c= 2.7.2 - Missing Authorization to Authenticated (Contributor+) Limited File Upload via Kubio Block Attributes"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "assignerShortName": "Wordfence",
        "cveId": "CVE-2026-5427",
        "datePublished": "2026-04-17T03:36:44.993Z",
        "dateReserved": "2026-04-02T14:24:35.903Z",
        "dateUpdated": "2026-04-17T18:48:57.774Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON
How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

Loading timeline…




    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.