AWS v1.0.11 Patch Stops Serverless CI/CD Pushers from Escalating Privileges via IAM Flaw
A flaw in AWS CICD-toolchain-for-serverless-applications versions 1.0.7 through 1.0.10 let repository pushers access external resources in the same account.
Key points
- CVE-2026-112407 allows authenticated users with push access to escalate privileges via the toolchain pipeline.
- The vulnerability stems from an incorrect privilege assignment in the application's IAM policy.
- Users must upgrade to version 1.0.11 or later to mitigate the risk of accessing resources outside the application stack.
Attackers with push access to the source repository of an AWS serverless application can now escalate privileges to access or modify resources outside the application stack. This capability exists in versions 1.0.7 through 1.0.10 of the CICD-toolchain-for-serverless-applications. The flaw allows remote authenticated users to exploit application templates deployed by the toolchain pipeline.
In plain English
The issue arises because the IAM policy assigned too many permissions to the CI/CD pipeline components. When a user with push access submits code, the pipeline processes that code using elevated privileges. This incorrect privilege assignment means that actions taken within the pipeline can affect resources that are not part of the specific serverless application stack.
The background
AWS released a security bulletin on October 20, 2026, detailing CVE-2026-112407. The company classified the issue as important and requiring attention. The vulnerability affects the sample application that provisions a CI/CD pipeline for serverless applications through the AWS Serverless Application Repository. Changli from Xidian University reported the issue through the coordinated vulnerability disclosure process.
What changes now
AWS has addressed the problem in version 1.0.11 of the CICD-toolchain-for-serverless-applications. The vendor recommends that users upgrade their existing toolchain stacks to version 1.0.11 or later. Organizations that have forked or created derivative code based on the earlier versions must also patch their custom implementations to incorporate the new fixes.
What made it possible
Teams usually audit IAM policies for CI/CD pipelines to ensure least privilege access. Incorrect privilege assignment often occurs when developers grant broad permissions to automate deployment tasks without restricting scope. Check whether your pipelines have permissions to modify resources outside their designated stack. This stage of an intrusion serves to expand lateral movement capabilities within the same account after initial access is gained through repository push rights.
What to do and how to stay safe: AWS
- Identify all instances of CICD-toolchain-for-serverless-applications in your AWS accounts and check their current version numbers.
- Upgrade any toolchain stacks running versions 1.0.7 through 1.0.10 to version 1.0.11 or later to apply the vendor's fix.
- Review any forked or derivative code based on the toolchain to ensure it incorporates the privilege assignment corrections.
- Monitor access logs for unusual activity in the CI/CD pipeline that might indicate exploitation of the incorrect privilege assignment before patching.
Step-by-step guide: Automatic Updates Mistakes That Leave Systems Exposed
General security guidance from the RedTeam Monitor newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is the CVSS score for CVE-2026-112407?
The National Vulnerability Database rates CVE-2026-112407 as CVSS 8.8, which is classified as HIGH severity.
Which versions of the toolchain are affected by this flaw?
Versions 1.0.7 through 1.0.10 of the AWS CICD-toolchain-for-serverless-applications are affected by this incorrect privilege assignment.
Is there a fix available for this vulnerability?
Yes, AWS has released version 1.0.11, which addresses the issue. Users should upgrade their stacks to this version or later.
