CVE-2026-58202

Full vulnerability record from the local CVENow database.

Description

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 2.0.0, the account-confirmation link in emails is built from the request Host header, with no allowlist. The unauthenticated POST /api/auth/resend-confirmation rotates a pending invitee's confirmation token and emails a link whose host comes from the request. An attacker who sends one resend-confirmation with Host: attacker.example and a pending invitee's email causes that invitee to receive a confirmation email whose only link points to the attacker. If the invitee clicks, the one-time confirmation token reaches the attacker, who then confirms the account on the real tenant domain and registers a passkey they control, taking over the account before the legitimate invitee ever uses it. All released versions through v1.1.0 are affected; no patched version exists yet. Reaching the app with a spoofed Host depends on the front proxy: the stock Caddy catch-all forwards it, while an operator who configures explicit per-tenant proxy blocks is not affected (see Details 4). The invite path builds links from the trusted tenant.domain (invite/+server.ts:204-210); the resend-confirmation path builds them from the request Host. This issue has been patched in version 2.0.0.

Severity

HIGH

CVSS score

8.3 (v3.1)

Vulnerability status

Deferred

Source identifier

[email protected]

Published

2026-10-23 21:17:24.473000

Last modified

2026-10-29 19:17:23.980000

View original CVE JSON

{
  "id": "CVE-2026-58202",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-23T21:17:24.473",
  "lastModified": "2026-10-29T19:17:23.980",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 2.0.0, the account-confirmation link in emails is built from the request Host header, with no allowlist. The unauthenticated POST /api/auth/resend-confirmation rotates a pending invitee's confirmation token and emails a link whose host comes from the request. An attacker who sends one resend-confirmation with Host: attacker.example and a pending invitee's email causes that invitee to receive a confirmation email whose only link points to the attacker. If the invitee clicks, the one-time confirmation token reaches the attacker, who then confirms the account on the real tenant domain and registers a passkey they control, taking over the account before the legitimate invitee ever uses it. All released versions through v1.1.0 are affected; no patched version exists yet. Reaching the app with a spoofed Host depends on the front proxy: the stock Caddy catch-all forwards it, while an operator who configures explicit per-tenant proxy blocks is not affected (see Details 4). The invite path builds links from the trusted tenant.domain (invite/+server.ts:204-210); the resend-confirmation path builds them from the request Host. This issue has been patched in version 2.0.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "open-reception",
          "product": "appointment-booking-software",
          "versions": [
            {
              "version": "< 2.0.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L",
          "baseScore": 8.3,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 5.5
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-29T18:16:21.166284Z",
          "id": "CVE-2026-58202",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-640"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/open-reception/appointment-booking-software/commit/df5432776a1a5b47c3a64d64e9d05dbe2b7a7819",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/open-reception/appointment-booking-software/releases/tag/v2.0.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/open-reception/appointment-booking-software/security/advisories/GHSA-w5g9-g2p4-2g4m",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/open-reception/appointment-booking-software/security/advisories/GHSA-w5g9-g2p4-2g4m",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}