RCE in AWS Trusted-Remote-Execution

CVE-2026-122193

OS command injection in the example SSM document provisioning script in Trusted Remote Execution (REX) before 2026-07-28 might allow an authenticated remote user who is permitted to invoke the Rex-RO or Rex-RW SSM document to execute arbitrary commands as root on the managed instance, bypassing Cedar policy enforcement. To remediate this issue, users should delete any Rex-RO and Rex-RW SSM documents created from the example script, in each account and Region where it was run.

Vulnerability class: Command Injection (OS Command Injection)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-122193?
CVE-2026-122193 is a critical-severity vulnerability in AWS Trusted-Remote-Execution, classified under OS Command Injection. CVSS score: 9.9/10. Published 2026-11-06.
How severe is CVE-2026-122193?
Critical severity. CVSS v3 base score is 9.9 out of 10.