SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAwaiting Analysis

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…

CRITICAL 10.0EPSS 2.49%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (2.49%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 4.0
10.0 CRITICALCVSS:4.0/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/M
EPSS
2.49% probability · 85th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-306, CWE-1188
Source
ff89ba41-3aa1-4d27-914a-91399e9639e5
EPSS trend
0%3%5%3 October 2026: 0.47%23 October 2026: 1.70%27 October 2026: 2.49%3 October 202627 October 2026

EPSS moved from 0.5% on 3 October 2026 to 2.5% on 27 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.