Vulnerability · Published Sep 10, 2026 · Assigned by AMZN
CVE-2026-89049Server-side request forgery in the Session Manager port forwarding functionality in AWS Systems Manager Agent
Critical 9.9
In plain English
A critical-severity server-side request forgery in Amazon SSM Agent from AWS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 52% of all known vulnerabilities).
Official description
A server-side request forgery issue due to improper validation of equivalent address representations in the port forwarding to remote hosts functionality in Amazon AWS Systems Manager Agent (SSM Agent) before 3.3.4851.0 on all platforms might allow an authenticated remote user to bypass the remote destination denylist and reach link-local endpoints, potentially obtaining the temporary IAM role credentials of a managed instance and acting with that role's permissions from outside the instance, via a crafted destination host value that uses an alternate representation of a denied link-local address. To remediate this issue, users should upgrade to version 3.3.4851.0 or later.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| AWS | Amazon SSM Agent | 0 – before 3.3.4851.0 |
Weakness: CWE-918, CWE-1289 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H