Description
OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.2, a TENANT_ADMIN can store `javascript:` URLs in the tenant `links` configuration (`website`, `imprint`, `privacyStatement`). These values are returned to the patient-facing landing page via `/api/public`, hydrated into the SvelteKit Button component, and rendered as `<a href="javascript:...">` elements without URL-scheme filtering. A patient who clicks any such link executes the attacker's JavaScript inside the patient browser origin, where patient form data is read before client-side encryption is applied. This breaks the project's central trust claim that the server is an untrusted relay and that administrators cannot read patient data. Patient-side encryption happens after form input, so JavaScript executing in the patient origin can read or alter the plaintext before encryption is performed. Version 1.0.2 fixes the issue.
References3
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 16 · as of 12 November 2026
- CWE
- CWE-79
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