External risk intelligence

go-base JWT Signing Secret Hardcoded Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.1)

CVE-2026-48031

The vulnerability exists in a RESTful API boilerplate template designed to be used as a backend service. APIs built on such frameworks are commonly deployed as internet-facing services or public-facing API endpoints in typical deployments.

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 vulnerability in a Go RESTful API boilerplate template, go-base, allows attackers to forge authentication tokens and bypass security controls by exploiting a hardcoded secret. This could enable unauthorized access to protected resources and user data. The issue affects versions prior to May 18, 2026.

Hardcoded secret allows unauthorized access.
Boilerplate code is widely reused, increasing exposure.
Confirm if your applications use this boilerplate template.

Attack Path

How an attacker could exploit the issue

An attacker could gain unauthorized access to protected areas of an application by forging authentication tokens. This is possible because the secret used to sign these tokens was publicly known and easily discoverable. Once an attacker can create valid tokens, they can impersonate any user, including administrators, and access sensitive data or perform actions without needing to authenticate legitimately.

Attacker reads public code repository.
Attacker forges JWT tokens using known secret.
Bypasses authentication, accesses protected endpoints.

Live Threat

Current exploitation, exposure, and threat context

When supported by the advisory, an attacker could forge authentication tokens to bypass access controls on protected API endpoints. This could allow unauthorized access to user data and service functions.

API authentication tokens.
Unprotected code repository access.
Unauthorized access to user data.

Operational Fix

Recommended remediation, mitigation, and detection steps

Ownership of this critical vulnerability likely falls to the application development or platform teams responsible for the go-base template and any applications built using it. The first practical step is to identify all instances of the affected boilerplate, confirm their reachability and criticality, and then coordinate with the relevant application owners to plan remediation.

Application development/platform teams own this.
Verify all affected deployments exist.
Plan remediation based on criticality.

Supplementary metadata

CVSS vector

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Frequently asked questions

What is go-base and why is it used?

go-base is a foundational template designed for developers to quickly build Go-based RESTful APIs. It includes essential features like JWT-based authentication and PostgreSQL database integration. Because it provides a pre-configured architecture, it is frequently used as a starting point for backend services, meaning many different applications may rely on its default settings and code structures.

How does CWE-798 manifest in CVE-2026-48031?

This vulnerability is a classic case of Use of Hardcoded Credentials (CWE-798). The affected software used the predictable string "random" as the secret key to digitally sign authentication tokens. Because this secret was embedded directly into the source code, anyone with access to the code could use it to create valid, forged tokens, effectively tricking the application into granting them full access as if they were a legitimate, authenticated user.

Does this vulnerability trigger if I use a custom .env file?

No, simply having a .env file is not enough to stop this. Even if you define your own settings, the application contained a programmatic fallback in the source code that would revert to the hardcoded "random" secret if it failed to load the environment file correctly. This ensured that the insecure default remained active in many deployments, regardless of whether a configuration file was present.

Is my application at risk according to Halo Surface Signal?

Halo Surface Signal identifies this as a 'Likely' risk because go-base is specifically designed to create backend services. These APIs are commonly deployed as internet-facing components. If your service built on this template is reachable from the public internet, an attacker can discover the hardcoded secret from the public repository and use it to bypass your authentication controls remotely.

What should I do to secure my application?

First, verify if your projects are built using go-base versions prior to May 18, 2026. If they are, you must update to the patched version immediately. Since previous versions used insecure secrets, assume any existing tokens could have been compromised; after updating the code to use a secure, randomly generated, and properly managed secret, you should invalidate all current user sessions to ensure the new security controls are fully enforced.

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.