OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. In versions 2.1.0 and prior, an unauthenticated attacker can store an arbitrary ML-KEM-768 public key under any existing user's identity in any tenant's staff-crypto recipient directory. The product's design guarantees that appointment data is end-to-end encrypted to staff members and that the staff recipient directory is not attacker-writable, so that even administrators and the operator cannot read patient data. This endpoint breaks that guarantee for an unauthenticated remote actor: it allows writing an arbitrary encryption recipient into the recipient directory of any tenant. The injected key receives the tunnel key of every appointment booked afterward in that tenant, because booking clients encrypt to all active staff keys. The attacker holds the corresponding secret key and is a persistent, unauthorized recipient of that key material. At time of publication, there are no publicly available patches.

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 2.2.2, an attacker overbooks an agent, placing multiple appointments into a single time slot that the system is designed to keep exclusive. The number of overlapping appointments equals the number of concurrent requests, and one booking token is enough because the token is consumed after the insert. This results in the integrity of the booking-calendar breaking and availability being denied to other clients. This issue has been patched in version 2.2.2.

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. In versions 2.1.0 and prior, a returning client's six-digit booking PIN can be brute-forced online in the victim tenant. A successful guess yields the client's booking access token, granting access to that client's appointment tunnel, which holds their end-to-end-encrypted appointment data, and the ability to act as the client, for example adding or cancelling appointments in the tunnel. The bypass is cross-tenant: state owned by one tenant removes an authentication protection of a different tenant. This crossing of the tenant boundary is the basis for the scope-changed vector. At time of publication, there are no publicly available patches.

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 2.2.1, an attacker who captures a pending invite token can replay it to obtain a passkey-registration credential and register their own passkey on the invited account, taking control of that account. For a staff or tenant-admin invite this yields access to the tenant context tied to that account. This issue has been patched in version 2.2.1.

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.

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.4, the route POST /api/tenants/{tenantId}/staff/{staffId}/crypto accepts and stores attacker-controlled ML-KEM-768 public keys against any tenant on the platform without authentication. The handler logs an "Unauthorized crypto key storage attempt" warning when neither a session nor a registration cookie is present, then proceeds to insert the row regardless. The platform's E2E claim that "even administrators cannot view sensitive information" is broken: any unauthenticated network attacker can register themselves as an additional encryption recipient for any tenant's future patient appointments. A second variant of the bug suppresses the unauthorized-warning log entry. The Zod schema makes the email field optional. When the request body omits email and the request carries no registration cookie, the comparison registrationEmail === email becomes undefined === undefined, which evaluates to true. The handler treats the request as a legitimate registration flow, skips the warning entirely, and stores the row. Successful storage is still recorded as an [info] log line, but the security-relevant warning that operators are most likely to monitor or alert on is gone. The staffcrypto table has no unique constraint on userid, so an arbitrary number of attacker rows can coexist for the same staff identifier and all return as isactive=true. The supplied staffId does not need to match any existing user or pending invite. Schema validation on passkeyId, publicKey, and privateKeyShare is also weak: the literal string <placeholder-base64> was accepted, indicating no length, format, or cryptographic-validity check beyond field presence. This weakness is independent of the auth bypass but compounds it: a poisoned directory can also be filled with malformed entries that break legitimate booking flows. The injected key is consumed by the public booking flow. After completing the unauthenticated bootstrap-challenge and bootstrap-verify ceremony as a "patient", the resulting bookingAccessToken is accepted by GET /api/tenants/{id}/appointments/staff-public-keys, which returns the attacker-controlled keys alongside any legitimate ones. A new appointment encrypts its tunnel key with ML-KEM to all listed recipients, so the attacker becomes a co-recipient of the encryption and can decapsulate the tunnel key with the matching secret. From there, all appointment payloads for that booking are decryptable. Version 1.0.4 patches the issue.