External risk intelligence

Authenticated User Profile Pivot Vulnerability in myGardyn Cloud API.

CVE advisorySeverity: CRITICAL (CVSS 9.3)

CVE-2026-25197

The vulnerability exists within a cloud API product. As a cloud-hosted API service, this component is designed to be internet-accessible by users and client applications, making it a commonly exposed internet-facing surface.

Mygardyn Cloud Api

before 2.12.2026

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability has been identified in the mygardyn cloud API, allowing authenticated users to access other user profiles by altering specific API call parameters. This could potentially expose sensitive user data or allow unauthorized actions across different accounts. The main concern is confirming if your organization utilizes this specific API and, if so, understanding the extent of your exposure.

Authenticated users can access other profiles.
Confirm usage and exposure to mygardyn cloud API.
Understand potential for unauthorized data access.

Attack Path

How an attacker could exploit the issue

An attacker could gain unauthorized access to other user accounts by exploiting a vulnerability in a specific API endpoint. This endpoint, designed for authenticated users, incorrectly allows them to change a user ID within an API call to access different profiles. This could potentially lead to broad unauthorized data access or manipulation if exploited.

Requires authenticated user access.
Modify user ID in API call.
Access other users' data.

Live Threat

Current exploitation, exposure, and threat context

Authenticated users could potentially access or modify data belonging to other users by manipulating API calls. This occurs when the system allows a user to change an identifier within an API request to target a different user's profile.

User profile data at risk.
ID manipulation in API calls.
Unauthorized access to other profiles.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in the mygardyn cloud API allows authenticated users to access other user profiles by manipulating API calls. Real-world responsibility likely falls to the platform or cloud infrastructure team managing the API, in coordination with the vendor (mygardyn) and potentially a security operations team for initial exposure review. The first practical step is to identify all instances of the affected API, confirm its reachability and business criticality, and then engage the platform owner to plan remediation, likely involving vendor coordination or an emergency patch deployment if the risk is significant.

Platform or cloud infrastructure team owns remediation.
Verify API reachability and business criticality.
Coordinate with vendor for patch or workaround.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the myGardyn cloud_api?

The myGardyn cloud_api is a cloud-hosted service used by the myGardyn ecosystem to manage user profiles, data, and interconnected system operations. It serves as the backend interface through which client applications communicate to retrieve or update account information.

What does CVE-2026-25197 mean in plain English?

This vulnerability is classified as CWE-639, or Authorization Bypass Through User-Controlled Key. It means the system fails to properly verify if a user has permission to access the profile they are requesting. By simply changing an ID number in an API request, an authenticated user can trick the system into revealing or modifying information belonging to another person.

How can an attacker trigger this vulnerability?

The flaw is triggered when an already authenticated user submits an API request that targets an incorrect user ID. The system trusts this input without verifying ownership. Importantly, an unauthenticated user—someone without a valid session or account—cannot trigger this bug, as the vulnerability requires access to the API endpoints reserved for authorized users.

Why is myGardyn cloud_api flagged as internet-facing?

Halo Surface Signal flags this as internet-facing because the myGardyn cloud_api is a cloud-hosted service. By design, these APIs must be reachable over the network for client applications and users to function, which places the affected endpoints on the public-facing surface of your infrastructure.

What is the first step for those using this technology?

Begin by identifying all deployments of the affected myGardyn cloud_api within your environment. Once you have an inventory, work with your platform or infrastructure team to verify the API's current reachability and business criticality, then coordinate directly with the vendor for the necessary security updates to resolve the underlying authorization flaw.

References

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.