Critical 9.9Published Sep 10, 2026

CVE-2026-89049Server-side request forgery in the Session Manager port forwarding functionality in AWS Systems Manager Agent

Updated under an hour ago (2026-10-19 06:30 UTC)

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It affects AWS Amazon SSM Agent. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for AWS Amazon SSM Agent

Exploited in the last 30 days

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.

CVSS: 9.9 CRITICAL (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weakness (CWE): CWE-918, CWE-1289
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: AMZN
NVD analysis: Awaiting Analysis
Record last updated: Sep 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

AWS Amazon SSM Agent aws:amazon_ssm_agent (from the name)	before 3.3.4851.0	CNA record

References

https://github.com/aws/amazon-ssm-agent/releases/tag/3.3.4851.0patch
https://aws.amazon.com/security/security-bulletins/2026-107-aws/vendor-advisory
https://github.com/aws/amazon-ssm-agent/security/advisories/GHSA-w9jw-h72g-6hxcthird-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.