open-reception appointment-booking-software up to 2.1.0 improper authorization

Summaryinfo

A vulnerability classified as critical was found in open-reception appointment-booking-software up to 2.1.0. This issue affects some unknown processing. Executing a manipulation can lead to improper authorization. The identification of this vulnerability is CVE-2026-75525. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as critical was found in open-reception appointment-booking-software up to 2.1.0. This vulnerability affects an unknown function. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is available at github.com. This vulnerability was named CVE-2026-75525 since 08/17/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 10/23/2026). This vulnerability is assigned to T1548.002 by the MITRE ATT&CK project.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-109159). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Appointment Software

Vendor

• open-reception

Name

• appointment-booking-software

Version

• 2.0
• 2.1.0

Website

• Product: https://github.com/open-reception/appointment-booking-software/

CPE 2.3info

• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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