External risk intelligence

Loom for AWS Super-Admin Authority Exploit Via Unauthenticated API Access.

CVE advisorySeverity: CRITICAL (CVSS 10.0)

CVE-2026-103956

The vulnerability affects the API of an application (Loom for AWS) that manages agent control planes and integration credentials. API endpoints for such management services are commonly deployed as network-accessible services to facilitate interaction with managed resources, making them likely to be reachable in environments where the service is exposed for operational utility.

Missing Authentication

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 security vulnerability in Loom for AWS could allow unauthorized remote actors to gain super-admin privileges, potentially enabling them to register tool servers, access integration credentials, and alter critical IAM policies. This could occur in deployments where no identity provider is configured.

Critical system access potentially compromised.
Leadership should track vendor security for connected systems.
Confirm relevance and exposure of this specific software.

Attack Path

How an attacker could exploit the issue

Attackers could exploit this by sending requests directly to the application's API if no identity provider is configured. This bypasses authentication and grants them significant control over the agent control plane, allowing them to register tool servers, access sensitive credentials, and alter critical security policies.

No identity provider is configured.
Any request to the application API.
Gains super-admin authority over the control plane.

Live Threat

Current exploitation, exposure, and threat context

In deployments lacking an identity provider, remote actors could achieve super-admin privileges over the agent control plane by exploiting a missing authentication check in a critical function. This could allow them to register tool servers, access stored integration credentials, and modify IAM role policies associated with managed agent roles.

Data/System Asset at Risk: Agent control plane, integration credentials.
How Exposure Could Happen: Unauthenticated API requests.
Realistic Consequence: Unauthorized system control.

Operational Fix

Recommended remediation, mitigation, and detection steps

This critical vulnerability in Loom for AWS impacts organizations using the agent control plane, particularly those without an identity provider configured. Application owners, in coordination with infrastructure or platform teams, are responsible for assessing exposure and planning remediation. The first practical step involves identifying all instances of the affected technology, confirming its reachability and business criticality, and then engaging the accountable owner to prioritize and schedule the upgrade to a non-vulnerable version.

Identify affected instances and owners.
Verify network exposure and criticality.
Plan and execute upgrade to 1.6.1+.

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.

Free EASM Trial See How Signal Works

Frequently asked questions

What is Loom for AWS?

Loom for AWS is a specialized software tool designed to manage agent control planes. It acts as an orchestration layer, allowing users to register tool servers, manage sensitive integration credentials, and configure IAM role policies for managed agents, effectively centralizing the administrative tasks for these distributed components.

What does CVE-2026-103956 mean by missing authentication?

This vulnerability, classified as CWE-306, occurs when a software system fails to verify the identity of a user before granting access to critical functions. In this case, the application's authentication dependency does not properly challenge incoming requests, allowing anyone who reaches the API to interact with sensitive administrative features as if they were a super-admin.

How can an attacker trigger this vulnerability?

An attacker triggers this by sending unauthorized requests directly to the application's API. Importantly, this issue specifically impacts deployments where no identity provider has been configured. If your deployment has an identity provider actively enforcing authentication, the vulnerability is not reachable via this specific bypass path.

Do I need to worry if my instance is internal?

According to Halo Surface Signal, this vulnerability affects an API designed to facilitate interactions with managed resources, meaning it is often deployed in ways that are network-accessible. While internet-facing instances are at higher risk, you should verify if your internal network access controls are sufficient to prevent unauthorized API requests from reaching the service.

How should I respond to CVE-2026-103956?

Your first step is to locate all instances of Loom for AWS within your environment to determine if they are currently unauthenticated. Once identified, coordinate with your infrastructure team to verify their configuration and exposure. Finally, prioritize updating all affected instances to version 1.6.1 or later to implement the necessary authentication fixes.

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.