CVE-2026-22611Network attack vector

Request disclosure via invalid region hostname

Published Jan 10, 2026 · Updated Jan 10, 2026

Improper input validation in AWS SDK for .NET 4.0.0 through 4.0.3.2 allows attackers to redirect AWS API calls to non-AWS hosts. ClientConfig used a resolved region to construct an endpoint URL without first ensuring that the value was a valid DNS host label. Exploitation requires control of the application's region input or environment, and redirected requests can expose request data to an attacker-controlled host.

CVSS severity3.7
Low
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in AWS SDK for .NET 4.0.0 through 4.0.3.2 allows attackers to redirect AWS API calls to non-AWS hosts. ClientConfig used a resolved region to construct an endpoint URL without first ensuring that the value was a valid DNS host label. Exploitation requires control of the application's region input or environment, and redirected requests can expose request data to an attacker-controlled host.

The record

CVE
CVE-2026-22611
Published
Jan 10, 2026
Updated
Jan 10, 2026
Vendor
Amazon Web Services
Product
AWS SDK for .NET
Classifications
CWE-20
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 4.0.0, < 4.0.3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Amazon Web Services · AWS SDK for .NETversion=>= 4.0.0, < 4.0.3.3

Published CVSS scores

3.7GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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