OpenReception appointment-booking-software up to 1.0.4 add-to-tunnel tunnelId/emailHash improper authorization

Summaryinfo

A vulnerability classified as critical was found in OpenReception appointment-booking-software up to 1.0.4. Impacted is an unknown function of the component add-to-tunnel. The manipulation of the argument tunnelId/emailHash results in improper authorization. This vulnerability is known as CVE-2026-48075. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability classified as critical has been found in OpenReception appointment-booking-software up to 1.0.4. Affected is an unknown function of the component add-to-tunnel. The manipulation of the argument tunnelId/emailHash with an unknown input leads to a improper authorization vulnerability. CWE is classifying the issue as CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. This is going to have an impact on integrity, and availability. CVE summarizes:

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.5, the `add-to-tunnel` endpoint creates a new appointment row in any client tunnel without any caller authentication. A request that supplies any valid `tunnelId` and any valid `emailHash` (the two need not belong to the same tunnel) results in an inserted appointment with `status = "CONFIRMED"`, attacker-controlled ciphertext fields, attacker-controlled date and duration, and an attacker-chosen agent. The endpoint validates only that some tunnel exists with the given `emailHash`, then writes the appointment using the attacker-supplied `tunnelId` directly. The `emailHash` lookup is effectively an existence check on the tenant; it does not authenticate the caller as the owner of the supplied `tunnelId`. Combined with the absence of any session, Authorization header, booking access token, or PoW, this makes the endpoint accept arbitrary appointment writes into arbitrary tunnels. By contrast, the sibling endpoint `create-new-client` (used to bootstrap a brand-new client tunnel) requires a Bearer bootstrap booking access token issued by the bootstrap-challenge / bootstrap-verify flow. The `add-to-tunnel` endpoint, intended for return-clients booking additional appointments, has no equivalent gate. The application's own middleware confirms this is intentional: `add-to-tunnel` is explicitly listed in the apiAuthHandle public-route allowlist alongside the bootstrap and challenge endpoints (which legitimately have no session). Version 1.0.5 fixes the issue.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-48075 since 05/20/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1548.002.

Upgrading to version 1.0.5 eliminates this vulnerability.

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Productinfo

Type

• Appointment Software

Vendor

• OpenReception

Name

• appointment-booking-software

Version

• 1.0.0
• 1.0.1
• 1.0.2
• 1.0.3
• 1.0.4

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CPE 2.2info

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