Description
Improper neutralization of inputs used in an OS command in the FSx Windows File Server volume mounting component in Amazon ECS Agent on Windows before version 1.103.0 might allow a remote authenticated threat actor to execute shell commands with SYSTEM privileges on the underlying host via a specially crafted username field in an ECS task definition. This issue requires permissions to register ECS task definitions or write to the Secrets Manager or SSM Parameter Store credentials used by the FSx volume configuration. To remediate this issue, users should upgrade to version 1.103.0.
Affected products
amazon: amazon ecs container agent
References3
- aws.amazon.com/security/security-bulletins/2026-024-aws/ Vendor Advisory
- github.com/aws/amazon-ecs-agent/security/advisories/GHSA-fc67-c… Vendor Advisory
- github.com/aws/amazon-ecs-agent/releases/tag/v1.103.0 Release Notes
Metrics
- CVSS 3.1
-
7.2
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 4.0
-
7.5
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/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 - EPSS — exploit probability
- 1% percentile: 46 · as of 13 November 2026
- CWE
- CWE-78
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