SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-22611

From versions 4.0.0 to before 4.0.3.3, Customer applications could be configured to improperly route AWS API calls to non-existent or non-AWS hosts.

LOW 3.7EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

AWS SDK for .NET works with Amazon Web Services to help build scalable solutions with Amazon S3, Amazon DynamoDB, Amazon Glacier, and more. From versions 4.0.0 to before 4.0.3.3, Customer applications could be configured to improperly route AWS API calls to non-existent or non-AWS hosts. This notification is related to the use of specific values for the region input field when calling AWS services. An actor with access to the environment in which the SDK is used could set the region input field to an invalid value. This issue has been patched in version 4.0.3.3.

CVSS 3.1
3.7 LOWCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS
0.24% probability · 15th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-20
Source
security-advisories@github.com
EPSS trend
0%3%5%26 October 2026: 0.24%26 October 202626 October 2026

EPSS 0.2% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.