Skip to main content
Report · AWS Security BulletinsAbout CVE-2026-89049Published

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

Source AWS Security Bulletins

0
Authoritative record:CVE-2026-89049· Critical 9.9

Not known to be exploited · CVSS 9.9 Critical : upgrade to 3.3.4851.0 as a priority.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score
9.9Critical
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.6% chance of exploitation in 30 days – higher than 51% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in 3.3.4851.0
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 10 Sep 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade Amazon SSM Agent and aws/amazon-ssm-agent to 3.3.4851.0.

Affected software

ProductAffectedFixed in
AWSAmazon SSM AgentAffected
  • <3.3.4851.0
Fixed in
  • 3.3.4851.0
GitHubaws/amazon-ssm-agentpkg:github/aws/amazon-ssm-agentOther threatsAffected
  • <3.3.4851.0
Fixed in
  • 3.3.4851.0

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

A fix is available in AWS Systems Manager Agent version 3.3.4851.0. It is recommended to upgrade to this version to remediate the vulnerability. Until the upgrade is applied, restrict the use of the AWS-StartPortForwardingSessionToRemoteHost document by scoping IAM permissions to limit who can initiate port forwarding sessions.

Description

CVE-2026-89049 is a server-side request forgery (SSRF) vulnerability in the AWS Systems Manager Agent's Session Manager port forwarding feature. An authenticated user with port-forwarding permission can bypass the remote destination denylist due to improper validation of equivalent address representations. This allows the user to reach link-local endpoints and potentially obtain the managed instance's temporary IAM role credentials, enabling actions with those permissions from outside the instance. The vulnerability affects all versions prior to 3.3.4851.0. AWS has released version 3.3.4851.0 to fix this issue. Until upgrading, it is recommended to restrict the use of the AWS-StartPortForwardingSessionToRemoteHost document by scoping IAM permissions.

References

Community reviews

Loading reviews…