10.0
CRITICAL CVSS 4.0
CVE-2026-103956
Missing authentication for critical function in Loom for AWS
Description

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.

INFO

Published Date :

Oct. 2, 2026, 7:16 p.m.

Last Modified :

Oct. 2, 2026, 8:17 p.m.

Remotely Exploit :

Yes !

Source :

ff89ba41-3aa1-4d27-914a-91399e9639e5
Affected Products

The following products are affected by CVE-2026-103956 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 CRITICAL ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS 4.0 CRITICAL ff89ba41-3aa1-4d27-914a-91399e9639e5
CVSS 4.0 CRITICAL ff89ba41-3aa1-4d27-914a-91399e9639e5
Solution
Upgrade Loom for AWS to version 1.6.1 or later to fix authentication bypass.
  • Upgrade Loom for AWS to version 1.6.1 or later.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-103956.

URL 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
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-103956 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-103956 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-103956 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by ff89ba41-3aa1-4d27-914a-91399e9639e5

    Oct. 02, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/awslabs/loom/security/advisories/GHSA-vgmj-998f-r8mp
  • New CVE Received by ff89ba41-3aa1-4d27-914a-91399e9639e5

    Oct. 02, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
    Added CWE CWE-306
    Added CWE CWE-1188
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/103xxx/CVE-2026-103956.json">CVE-2026-103956</a>
    Added Reference https://aws.amazon.com/security/security-bulletins/2026-124-aws/
    Added Reference https://github.com/awslabs/loom/releases/tag/v1.6.1
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.