Vulnerability-Lookup

FKIE_CVE-2026-16624

Vulnerability from fkie_nvd - Published: 2026-07-22 19:16 - Updated: 2026-07-27 18:16

Severity

9.6 (Critical) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

Summary

Cal.com OSS ships lacks authorization on webhook teamId creation, allowing any authenticated user to create a webhook on any team via unvalidated teamId injection, then steal booking data, including fields like organizer/attendee emails and custom responses, and conditionally video-call passwords, by triggering webhook delivery.

References

	URL	Tags
	cret@cert.org	https://github.com/calcom/cal.diy/security/advisories/GHSA-4fwh-xxpv-xfm6
	cret@cert.org	https://vokecyber.com/research/calcom-cross-tenant-webhook-plant
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://vokecyber.com/research/calcom-cross-tenant-webhook-plant

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Cal.diy",
          "vendor": "Cal.com",
          "versions": [
            {
              "lessThan": "6.2.0",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "cret@cert.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Cal.com OSS ships lacks authorization on webhook teamId creation, allowing any authenticated user to create a webhook on any team via unvalidated teamId injection, then steal booking data, including fields like organizer/attendee emails and custom responses, and conditionally video-call passwords, by triggering webhook delivery."
    }
  ],
  "id": "CVE-2026-16624",
  "lastModified": "2026-07-27T18:16:52.807",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 9.6,
          "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:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 5.8,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-16624",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-27T17:09:33.166013Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-22T19:16:58.273",
  "references": [
    {
      "source": "cret@cert.org",
      "url": "https://github.com/calcom/cal.diy/security/advisories/GHSA-4fwh-xxpv-xfm6"
    },
    {
      "source": "cret@cert.org",
      "url": "https://vokecyber.com/research/calcom-cross-tenant-webhook-plant"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://vokecyber.com/research/calcom-cross-tenant-webhook-plant"
    }
  ],
  "sourceIdentifier": "cret@cert.org",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-639"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

CVE-2026-16624 (GCVE-0-2026-16624)

Vulnerability from cvelistv5 – Published: 2026-07-22 18:31 – Updated: 2026-07-27 17:10

Title

CVE-2026-16624

Summary

Severity

9.6 (Critical)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-27 17:09 UTC

CWE

CWE-639 Authorization Bypass Through User-Controlled Key
CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

certcc mitre root

References

2 references

URL	Tags
https://github.com/calcom/cal.diy/security/adviso…
https://vokecyber.com/research/calcom-cross-tenan…

Impacted products

1 product

Vendor	Product	Version
Cal.com	Cal.diy	Affected: 0 , < 6.2.0 (custom)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "NONE",
              "baseScore": 9.6,
              "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:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-16624",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-27T17:09:33.166013Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-639",
                "description": "CWE-639 Authorization Bypass Through User-Controlled Key",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-27T17:10:37.711Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://vokecyber.com/research/calcom-cross-tenant-webhook-plant"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Cal.diy",
          "vendor": "Cal.com",
          "versions": [
            {
              "lessThan": "6.2.0",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Cal.com OSS ships lacks authorization on webhook teamId creation, allowing any authenticated user to create a webhook on any team via unvalidated teamId injection, then steal booking data, including fields like organizer/attendee emails and custom responses, and conditionally video-call passwords, by triggering webhook delivery."
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "description": "CWE-639 Authorization Bypass Through User-Controlled Key",
              "lang": "en"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-22T18:31:30.694Z",
        "orgId": "37e5125f-f79b-445b-8fad-9564f167944b",
        "shortName": "certcc"
      },
      "references": [
        {
          "url": "https://github.com/calcom/cal.diy/security/advisories/GHSA-4fwh-xxpv-xfm6"
        },
        {
          "url": "https://vokecyber.com/research/calcom-cross-tenant-webhook-plant"
        }
      ],
      "source": {
        "discovery": "UNKNOWN"
      },
      "title": "CVE-2026-16624",
      "x_generator": {
        "engine": "VINCE 3.0.43",
        "env": "prod",
        "origin": "https://cveawg.mitre.org/api/cve/CVE-2026-16624"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b",
    "assignerShortName": "certcc",
    "cveId": "CVE-2026-16624",
    "datePublished": "2026-07-22T18:31:20.732Z",
    "dateReserved": "2026-07-22T15:02:38.700Z",
    "dateUpdated": "2026-07-27T17:10:37.711Z",
    "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.

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.

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.