CVE-2026-58202 (GCVE-0-2026-58202)
Vulnerability from cvelistv5 – Published: 2026-10-23 20:27 – Updated: 2026-10-29 18:16
VLAI
EPSS
VEX
Title
OpenReception: Confirmation-email links built from the request Host enable pending-account takeover via `POST /api/auth/resend-confirmation`
Summary
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
8.3 (High)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-29 18:16 UTC
CWE
- CWE-640 - Weak Password Recovery Mechanism for Forgotten Password
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/open-reception/appointment-boo… | x_refsource_CONFIRM |
| https://github.com/open-reception/appointment-boo… | x_refsource_MISC |
| https://github.com/open-reception/appointment-boo… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| open-reception | appointment-booking-software |
Affected:
< 2.0.0
|
guessed |
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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