External risk intelligence

VitaFit Cloud API Authentication Bypass Via Linked Account

CVE advisorySeverity: CRITICAL (CVSS 9.3)

CVE-2026-54384

The vulnerability exists in a cloud-based API endpoint (/front/login/sns/) designed to handle authentication via third-party identity providers. As a public-facing cloud API used for user authentication and login, this service is accessible over the internet by design to support application functionality.

Authentication Bypass

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

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

A critical vulnerability in the VitaFit cloud API allows remote attackers to bypass authentication by submitting linked social media identifiers without proof of ownership, potentially leading to account takeover, profile modification, or account deletion.

Unauthenticated access to user accounts.
Protects customer data and service availability.
Confirm relevance and verify exposure.

Attack Path

How an attacker could exploit the issue

An attacker can target the VitaFit cloud API to bypass authentication and gain unauthorized access to a victim's account. This is achieved by submitting a linked Google or Facebook account identifier to a specific API endpoint without verifying ownership. Once authenticated, the attacker can manipulate the victim's profile information, including potentially deleting their authentication records to lock them out.

No authentication required.
Submit linked social account identifier.
Compromise user account and profile.

Live Threat

Current exploitation, exposure, and threat context

A vulnerability in the VitaFit cloud API could allow remote attackers to gain unauthorized access to user accounts. This could occur by submitting a linked Google or Facebook account identifier to the login endpoint without proper verification. Once authenticated, an attacker could potentially view and alter a victim's profile information, and also lock the legitimate user out of their account by deleting the authentication record.

User profile data and account access.
Forged social login identifiers submitted to API.
Unauthorized profile changes and account lockout.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability in the VitaFit cloud API likely falls under the responsibility of the platform or application owner responsible for the `/front/login/sns/` endpoint. The first critical step is to identify all instances of this API, determine their reachability and business criticality, and locate the accountable owner before planning remediation.

Platform or application owners should lead.
Verify external API endpoint reachability.
Plan remediation with vendor coordination.

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 VitaFit application?

VitaFit is a health and fitness platform that connects mobile users to a cloud-based service. The software manages personal user profiles and relies on a cloud API to facilitate features like account login and synchronization between the mobile app and remote storage.

What is the vulnerability in CVE-2026-54384?

This issue is an Authentication Bypass, classified as CWE-290 (Authentication Bypass by Spoofing). It means the system incorrectly trusts identity information. Instead of verifying that a user truly owns a linked Google or Facebook account, the API accepts a submitted identifier as proof of identity, allowing an attacker to impersonate any user.

How does an attacker trigger this authentication bypass?

An attacker triggers this by sending a specific request to the /front/login/sns/ endpoint with a target user's social media identifier. The system does not require proof of ownership from the identity provider, so merely knowing an account ID is sufficient. Normal, valid login attempts through the official mobile app interface are not the source of this risk; the bug resides in how the API processes these direct, forged requests.

Why is this CVE considered relevant to my infrastructure according to Halo Surface Signal?

Halo Surface Signal identifies this as a critical concern because the affected component is a public-facing cloud API. Since this service must be accessible over the internet to handle remote logins for the mobile application, it is reachable by external actors without requiring specialized access to your internal network.

What should I do if I manage the VitaFit cloud environment?

Your first step is to confirm the reachability of the /front/login/sns/ endpoint within your infrastructure. Identify the team responsible for maintaining this API to ensure they are aware of the authentication flaw. Because this is a platform-level issue, you should focus on coordinating with the service owners to verify the security of identity verification processes before applying any vendor-supplied updates.

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.