External risk intelligence

Flyto2 Core SSRF and Secret Exfiltration Vulnerability.

CVE advisorySeverity: CRITICAL (CVSS 9.3)

CVE-2026-67426

The service listens on 0.0.0.0:8344 by default and exposes an unauthenticated POST endpoint. As a core automation and AI-agent workflow kernel component, services binding to all interfaces and providing unauthenticated functional endpoints are designed to be reachable and are commonly exposed as API endpoints in typical deployment patterns.

Missing Authentication

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

This advisory concerns a critical vulnerability in Flyto2 Core, an execution kernel for automation and AI-agent workflows. The issue, related to an unauthenticated service that handles verification, could allow unauthorized access to sensitive information and the execution of actions on external systems. Understanding the relevance of Flyto2 Core within your environment is the primary concern.

Unauthenticated access to sensitive data and actions.
Understand Flyto2 Core's role in your automated workflows.
Confirm relevance and assess potential exposure.

Attack Path

How an attacker could exploit the issue

An attacker can reach the vulnerable `flyto-verification` service over the network. By sending an unauthenticated POST request to the `/run` endpoint, they can manipulate the `callback_url` parameter. This allows them to trigger a server-side request to a location of their choice and potentially steal the runner secret.

No authentication required.
Triggered by manipulating callback URL.
Risk of secret exfiltration.

Live Threat

Current exploitation, exposure, and threat context

Unauthenticated users could trigger the verification service to make outbound requests to arbitrary URLs, potentially exposing the runner secret. This could occur when the verification service is running and accessible.

Runner secret and internal system data.
Unauthenticated POST request to verification service.
Unauthorized access to sensitive internal information.

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability impacts Flyto2 Core's verification service, likely managed by platform or application teams responsible for automation and AI workflows. The immediate first step is to inventory where Flyto2 Core is deployed, confirm its external reachability and business criticality, identify the accountable owner, and then prioritize remediation based on exposure.

Platform or application teams own this.
Verify external reachability and criticality.
Plan remediation based on confirmed risk.

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 Flyto2 Core?

Flyto2 Core is a specialized execution kernel designed to orchestrate automation tasks and AI-agent workflows. It provides the underlying processing power that allows these agents to perform complex, multi-step operations. It is commonly integrated into technical infrastructure to manage logic execution, often relying on internal services like the verification component to validate and route these automated requests.

What does CVE-2026-67426 mean?

This vulnerability involves three weakness classes: missing authentication, insufficient credential protection, and server-side request forgery (SSRF). In plain terms, the software fails to verify who is making a request to its verification service. This allows an unauthorized person to force the software to send data to an arbitrary destination of their choosing, which can accidentally reveal sensitive internal credentials used by the system.

How is this vulnerability triggered?

An attacker triggers the bug by sending a crafted POST request to the unauthenticated /run endpoint within the verification service. Because the service does not validate the input, an attacker can manipulate the callback_url parameter to redirect outbound traffic. Simply having the service running is the primary condition; the bug cannot be triggered if the service is disabled or if network-level access controls prevent reaching the specific verification endpoint.

Is my instance relevant according to Halo Surface Signal?

Yes, if you run this service, relevance is high. Halo Surface Signal notes that because the verification service binds to all network interfaces (0.0.0.0) by default on port 8344, it is often easily reachable. Since this component is central to automation and AI workflows, it is frequently exposed as an API endpoint. If your instance is reachable over the network, it is a primary target for this unauthorized access.

How do I respond to this vulnerability?

The first step is to inventory all deployments of Flyto2 Core within your environment to identify where the verification service is active. Check if these instances are reachable over your network and determine which team is responsible for managing them. Prioritize updating to version 2.26.7 or later to resolve the underlying flaw, and restrict network access to the verification endpoint until the update is applied.

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.