appointment-booking-software: Missing Authorization
CVE-2026-48088 is a critical-severity missing authorization vulnerability in appointment-booking-software from Open-reception, with a CVSS 3.1 base score of 9.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected appointment-booking-software versions: < 1.0.4. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.38% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of appointment-booking-software you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Open-reception | appointment-booking-software | < 1.0.4 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- LowPerformance or availability is reduced.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L. Scored by CNA (github.com).
Official description
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 `staff_crypto` table has no unique constraint on `user_id`, so an arbitrary number of attacker rows can coexist for the same staff identifier and all return as `is_active=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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Authorization
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
How developers prevent this class of flaw
- Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Patches and release notes
Other vulnerabilities in appointment-booking-software
- 7.5 High severity
- 7.4 High severity
- 8.3 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 9.9 Critical severity
Recent Missing Authorization vulnerabilities
- 7.5 High severity
- 7.6 High severity
- 9.8 Critical severity
- 7.1 High severity
- 7.1 High severity
- 7.5 High severity
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