Bulletin ID: AWS-2025-022
Scope: Amazon
Content Type: Important (requires attention)
Publication Date: 2025/10/09 11:00 AM PDT

Description:

Amazon.IonDotnet is a library for the Dotnet language that is used to read and write Amazon Ion data.

We identified CVE-2025-11573, which describes an infinite loop issue in Amazon.IonDotnet library versions <v1.3.2 that may allow a threat actor to cause a denial of service through a specially crafted text input. As of August 20, 2025, this library has been deprecated and will not receive further updates.

Affected versions: <1.3.2

Resolution:

This issue has been addressed in Amazon.IonDotnet version 1.3.2. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.

Workarounds:

Only accept data from trusted sources, written using a supported Ion library.

References:

• CVE-2025-11573
• GHSA-q5r6-9qwq-g2wj

Please email aws-security@amazon.com with any security questions or concerns.