# CVE-2026-103958 — AWS loom

> As of 2026-10-09, CVE-2026-103958 is a HIGH-severity vulnerability in AWS loom, CVSS v3.1 7.6, EPSS 0.3% (24.3th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-103958, most recently “AWS AI Agent Vulnerabilities (Loom, SageMaker Unified Studio) Let Attackers Bypass Authentication and Steal Credentials - CVE-2026-103956, CVE-2026-103957, CVE-2026-103958, CVE-2026-104019”.

**Last updated:** 2026-10-09

## What is CVE-2026-103958?

Server-side request forgery in the tool server and remote agent connection handling in Loom for AWS before 1.7.0 might allow an authenticated remote user to obtain the credentials of the application's own container role and to read responses from arbitrary internal network locations, via a crafted connection address supplied when registering, updating or testing a tool server or remote agent. To remediate this issue, users should upgrade to version 1.7.0 or later.

The record classifies CVE-2026-103958 under weakness class [CWE-918](https://intel.threadlinqs.com/cwe/CWE-918). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs high-privilege credentials, needs no user interaction, and has high impact on confidentiality. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 22 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.6 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:L/A:N`)
- **CVSS v4.0 base score:** 8.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:L/SA:N`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 24.3% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 4.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-10-02, last modified 2026-10-09

## Is CVE-2026-103958 being exploited?

It currently carries a trending score of 39 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [AWS](https://intel.threadlinqs.com/vendors/aws): loom

## How to fix CVE-2026-103958

No vendor patch reference has been recorded for CVE-2026-103958 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-103958

1 tracked threat in the Threadlinqs corpus references CVE-2026-103958, either in the campaign’s CVE list or as an indicator on the campaign record.

- [AWS AI Agent Vulnerabilities (Loom, SageMaker Unified Studio) Let Attackers Bypass Authentication and Steal Credentials - CVE-2026-103956, CVE-2026-103957, CVE-2026-103958, CVE-2026-104019](https://intel.threadlinqs.com/threat/TL-2026-2860) — CRITICAL · 2026-10-03

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10.

**Vendor advisory and patch**

- [github.com — release notes](https://github.com/awslabs/loom/releases/tag/v1.7.0)
- [aws.amazon.com — vendor advisory](https://aws.amazon.com/security/security-bulletins/2026-124-aws/)

**Third-party advisory**

- [github.com — third party advisory](https://github.com/awslabs/loom/security/advisories/GHSA-w6g6-h8pv-6mc7)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-103958
Full detection coverage and IOCs for threats exploiting CVE-2026-103958 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp