AWS Fixes Code Injection Flaw in Amplify Codegen UI React Library

Amazon Web Services released a security update on July 30, 2026, to address a code injection vulnerability in its Amplify Codegen UI React library. The company designated the issue as CVE-2026-18245 and published bulletin 2026-066-AWS to alert users of the risk and the available remediation path for affected projects.

The vulnerability exists within the amplify-codgen-ui-react package, which generates React components and themes from schema definitions for AWS Amplify projects. According to the advisory, an authenticated user could exploit this flaw to execute arbitrary JavaScript code during the component rendering and build process. The bulletin classifies the scope as important and requiring immediate attention.

Context and Background

AWS identified the issue and worked with George Chen, who reported the vulnerability through the coordinated disclosure process. The vendor thanked Chen for his collaboration in resolving the security concern. The advisory notes that the fix addresses the specific code injection path previously identified in the library’s build and rendering mechanisms.

There are no known workarounds for this vulnerability. The only recommended mitigation is to upgrade to the patched version. AWS stated that users must ensure any forked or derivative code is also patched to incorporate the new fixes, as standard upgrades may not automatically resolve issues in modified codebases.

Who Is Affected

Developers using the @aws-amplify/codegen-ui-react package in their AWS Amplify projects are affected by this vulnerability. The library is used to generate React components and themes from schema definitions, making it a common tool in frontend development workflows that rely on AWS Amplify services.

Any project utilizing versions prior to 2.20.6 is potentially exposed to arbitrary code execution if an authenticated user can interact with the component rendering or build process. Organizations that have forked the library or created derivative code must manually apply the fixes contained in the new release to their custom versions.

What should you do?

Security teams should immediately audit their projects for the presence of the @aws-amplify/codegen-ui-react package. If the package is present, verify the installed version against the patched release. Developers should update to version 2.20.6 as soon as possible to close the code injection vector.

For teams using forked or modified versions of the library, manual patching is required. Review the changes in version 2.20.6 and apply them to derivative code to ensure the arbitrary JavaScript execution flaw is mitigated. Monitor internal build logs for any signs of unexpected code execution during the rendering process.

What to do and how to stay safe: AWS

• Inventory all projects using @aws-amplify/codegen-ui-react to identify affected versions.
• Upgrade to version 2.20.6 immediately to mitigate the code injection risk.
• Manually patch any forked or derivative code to incorporate the security fixes.
• Monitor build and rendering logs for signs of arbitrary JavaScript execution.

Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger

General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.

Frequently asked questions

What is CVE-2026-18245?

It is a code injection vulnerability in the @aws-amplify/codegen-ui-react package that allows authenticated users to run arbitrary JavaScript code during component rendering and building.

Which version fixes this vulnerability?

Version 2.20.6 of the @aws-amplify/codegen-ui-react package contains the fix for CVE-2026-18245.

Are there any workarounds for this issue?

No, there are no workarounds. Users must upgrade to version 2.20.6 or manually patch derivative code.