---
cve: "CVE-2026-58202"
severity: "HIGH"
cvss: 8.3
epss: "0.2%"
vendor: "open-reception"
kev: false
exploited: false
published: "2026-10-23 20:27:36"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-27T10:04:58+01:00"
---

# CVE-2026-58202

> 8.3 HIGH · 🧪 PoC

## Beschreibung

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.

## CNA-Record (Kanon, cvelistV5)

- CNA: **GitHub_M**
- State: PUBLISHED
- Stand: 2026-10-23 20:27:36
- CNA-CVSS: **8.3** (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L`)

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Erforderlich | good |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Gering | warn |

## Schwachstellen-Klasse

- **CWE-640** — Weak Password Recovery Mechanism for Forgotten Password
  The product contains a mechanism for users to recover or change their passwords without knowing the original password, but the mechanism is weak.

## Angriffsmuster (CAPEC)

- [CAPEC-50 — Password Recovery Exploitation](https://capec.mitre.org/data/definitions/50.html) _(Severity: High)_

## Patch verfügbar (OSV)

- 51ef46d25d72c35bb4b69e018ddf64570668051b (Commit)
- df5432776a1a5b47c3a64d64e9d05dbe2b7a7819 (Commit)

## Referenzen

- <https://github.com/open-reception/appointment-booking-software/security/advisories/GHSA-w5g9-g2p4-2g4m>
- <https://github.com/open-reception/appointment-booking-software/commit/df5432776a1a5b47c3a64d64e9d05dbe2b7a7819>
- <https://github.com/open-reception/appointment-booking-software/releases/tag/v2.0.0>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-58202/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_