CVE-2026-103956

Missing authentication for critical function in the authentication dependency in Loom for AWS before 1.6.1 allowed remote actors to obtain super-admin authority over the agent control plane, including registering tool servers, reading stored integration credentials, and rewriting the IAM role policies attached to managed agent roles, via any request to the application API in a deployment where no identity provider is configured. To remediate this issue, users should upgrade to version 1.6.1 or later.

CVSS v3 10.0 CRITICAL

10.0^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://aws.amazon.com/security/security-bulletins/2026-124-aws/
https://github.com/awslabs/loom/releases/tag/v1.6.1
https://github.com/awslabs/loom/security/advisories/GHSA-vgmj-998f-r8mp

Configurations

No configuration.

History

02 Oct 2026, 20:17

Type	Values Removed	Values Added
References		() https://github.com/awslabs/loom/security/advisories/GHSA-vgmj-998f-r8mp -

02 Oct 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 19:16

Updated : 2026-10-06 14:49

NVD link : CVE-2026-103956

Mitre link : CVE-2026-103956

CVE.ORG link : CVE-2026-103956

JSON object : View

Products Affected

No product.

CWE

CWE-306

Missing Authentication for Critical Function

CWE-1188

Initialization of a Resource with an Insecure Default

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