Vulnerability-Lookup

GHSA-HM3P-9G7V-6RFW

Vulnerability from github – Published: 2026-10-01 06:31 – Updated: 2026-10-01 06:31

Details

The Simply Schedule Appointments plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.31 via the 'complete_group' parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with subscriber-level access and above, to disclose every co-booker's private per-appointment id_token (exposed as public_token) alongside their PII (name and email address), then use each leaked token to read, overwrite arbitrary appointment meta on, or cancel the co-booker's appointment via the same REST controller. Exploitation requires the attacker to possess a valid id_token for any single appointment within the targeted group booking.

Severity

6.5 (Medium)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-91109"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-10-01T04:18:21Z",
    "severity": "MODERATE"
  },
  "details": "The Simply Schedule Appointments plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.31 via the \u0027complete_group\u0027 parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with subscriber-level access and above, to disclose every co-booker\u0027s private per-appointment id_token (exposed as public_token) alongside their PII (name and email address), then use each leaked token to read, overwrite arbitrary appointment meta on, or cancel the co-booker\u0027s appointment via the same REST controller. Exploitation requires the attacker to possess a valid id_token for any single appointment within the targeted group booking.",
  "id": "GHSA-hm3p-9g7v-6rfw",
  "modified": "2026-10-01T06:31:23Z",
  "published": "2026-10-01T06:31:23Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91109"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-appointment-model.php#L1966"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-appointment-model.php#L2315"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-appointment-model.php#L3160"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-db-model.php#L348"
    },
    {
      "type": "WEB",
      "url": "https://plugins.trac.wordpress.org/changeset/3709365/simply-schedule-appointments/trunk/includes/class-appointment-model.php"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d1cd3de2-16ca-4f95-ad6f-47cfbe00c959?source=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-91109 (GCVE-0-2026-91109)

Vulnerability from cvelistv5 – Published: 2026-10-01 03:28 – Updated: 2026-10-01 03:28

Title

Simply Schedule Appointments <= 1.6.12.31 - Insecure Direct Object Reference to Authenticated (Subscriber+) Sensitive Information Disclosure via 'complete_group' Parameter

Summary

Severity

6.5 (Medium)


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

CWE

CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

Wordfence mitre root Scorecard

References

6 references

URL	Tags
https://www.wordfence.com/threat-intel/vulnerabil…
https://plugins.trac.wordpress.org/browser/simply…
https://plugins.trac.wordpress.org/browser/simply…
https://plugins.trac.wordpress.org/browser/simply…
https://plugins.trac.wordpress.org/browser/simply…
https://plugins.trac.wordpress.org/changeset/3709…

Impacted products

1 product

Vendor	Product	Version
croixhaug	Simply Schedule Appointments	Affected: 0 , ≤ 1.6.12.31 (semver)

Credits

jtb75

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Simply Schedule Appointments",
          "vendor": "croixhaug",
          "versions": [
            {
              "lessThanOrEqual": "1.6.12.31",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "jtb75"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "The Simply Schedule Appointments plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 1.6.12.31 via the \u0027complete_group\u0027 parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with subscriber-level access and above, to disclose every co-booker\u0027s private per-appointment id_token (exposed as public_token) alongside their PII (name and email address), then use each leaked token to read, overwrite arbitrary appointment meta on, or cancel the co-booker\u0027s appointment via the same REST controller. Exploitation requires the attacker to possess a valid id_token for any single appointment within the targeted group booking."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-639",
              "description": "CWE-639 Authorization Bypass Through User-Controlled Key",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-10-01T03:28:22.807Z",
        "orgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
        "shortName": "Wordfence"
      },
      "references": [
        {
          "url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d1cd3de2-16ca-4f95-ad6f-47cfbe00c959?source=cve"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-appointment-model.php#L3160"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-appointment-model.php#L1966"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-appointment-model.php#L2315"
        },
        {
          "url": "https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.12.27/includes/class-db-model.php#L348"
        },
        {
          "url": "https://plugins.trac.wordpress.org/changeset/3709365/simply-schedule-appointments/trunk/includes/class-appointment-model.php"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-09-14T19:51:27.000Z",
          "value": "Vendor Notified"
        },
        {
          "lang": "en",
          "time": "2026-09-30T15:10:42.000Z",
          "value": "Disclosed"
        }
      ],
      "title": "Simply Schedule Appointments \u003c= 1.6.12.31 - Insecure Direct Object Reference to Authenticated (Subscriber+) Sensitive Information Disclosure via \u0027complete_group\u0027 Parameter"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "b15e7b5b-3da4-40ae-a43c-f7aa60e62599",
    "assignerShortName": "Wordfence",
    "cveId": "CVE-2026-91109",
    "datePublished": "2026-10-01T03:28:22.807Z",
    "dateReserved": "2026-09-14T19:36:23.496Z",
    "dateUpdated": "2026-10-01T03:28:22.807Z",
    "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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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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.

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GHSA-HM3P-9G7V-6RFW

CVE-2026-91109 (GCVE-0-2026-91109)

Tags

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Nomenclature

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