CVE-2026-89049

Server-side request forgery in the Session Manager port forwarding functionality in AWS Systems Manager Agent

Published Sep 10, 2026 CVSS 4.0 · 8.5 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Server-side request forgery in the Session Manager port forwarding functionality in AWS Systems Manager Agent
First Time appeared Aws
Aws amazon Ssm Agent
Weaknesses CWE-1289
CWE-918
CPEs cpe:2.3:a:aws:amazon_ssm_agent:*:*:*:*:*:*:*:*
Vendors & Products Aws
Aws amazon Ssm Agent
References
Metrics cvssV3_1

{'score': 9.9, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H'}

cvssV4_0

{'score': 8.5, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
AMZN
Published
Updated
Sep 10, 2026, 6:57 PM
Reserved
Sep 10, 2026, 4:58 PM
Status
Awaiting Analysis
Published
Sep 10, 2026, 7:17 PM
Modified
Sep 10, 2026, 7:44 PM