Key points
- CVE-2026-112407 affects versions 1.0.7 through 1.0.10 of the AWS sample application.
- The flaw allows remote authenticated users with repository push access to access resources outside the application stack.
- AWS released version 1.0.11 to remediate the incorrect privilege assignment in the IAM policy.
AWS has released a patch for a high-severity vulnerability in its CICD-toolchain-for-serverless-applications sample application. The fix addresses an incorrect privilege assignment that could allow attackers to escalate their permissions within an AWS account.
What happened
The vulnerability, tracked as CVE-2026-112407, was identified in the IAM policy of the AWS CICD-toolchain-for-serverless-applications. According to the National Vulnerability Database, the flaw carries a CVSS score of 8.8, which is rated as high severity. The issue exists in versions 1.0.7 through 1.0.10 of the toolchain.
AWS describes the component as a sample application that provisions a CI/CD pipeline for serverless applications via the AWS Serverless Application Repository. The security bulletin, published on 20 October 2026, confirms that the incorrect privilege assignment allows remote authenticated users to exploit the system.
An attacker needs push access to the application source repository to exploit this flaw. By leveraging application templates deployed by the toolchain pipeline, such a user can escalate privileges. This escalation enables them to access or modify resources outside the specific application stack but within the same AWS account.
Why it matters
The impact of CVE-2026-112407 extends beyond the immediate application stack. Because the flaw allows access to resources outside the stack in the same account, organisations using this sample toolchain face potential lateral movement risks.
AWS classifies the bulletin as important and requiring attention. The vendor notes that the issue has been addressed in version 1.0.11. Users are advised to upgrade existing toolchain stacks to this version or later.
AWS also recommends ensuring that any forked or derivative code is patched to incorporate the new fixes. The vendor thanked Changli from Xidian University for collaborating on the issue through the coordinated vulnerability disclosure process.
What happens next
- Identify all instances of the CICD-toolchain-for-serverless-applications in your environment.
- Verify the current version of each deployment to check if it falls between 1.0.7 and 1.0.10.
- Upgrade affected stacks to version 1.0.11 or later using the AWS Serverless Application Repository.
- Review any custom forks or derivative code to ensure they include the security fixes from the official update.
Patch priority
Teams should prioritise updating systems that are exposed to external contributors or third-party developers with repository push access. Start by auditing which accounts use the affected sample application and whether those repositories have broad write permissions. Test the upgrade in a non-production environment first to ensure pipeline stability. Back up existing configurations before applying changes. If immediate updating is not feasible, restrict repository access to trusted internal staff only to reduce the attack surface while planning the remediation rollout.
What to do and how to stay safe: AWS
- Audit all CI/CD pipelines to identify any use of the AWS CICD-toolchain-for-serverless-applications sample code.
- Check version numbers against the affected range of 1.0.7 through 1.0.10 to determine exposure.
- Restrict push access to source repositories used by these toolchains to minimise the risk of exploitation.
- Monitor AWS security bulletins for updates on this issue and apply the vendor-provided patch once available.
Step-by-step guide: Patch Management: Definition, Purpose and Operational Reality
General security guidance from the AppSec Scoop newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
Which versions of the AWS CICD-toolchain are affected by CVE-2026-112407?
Versions 1.0.7 through 1.0.10 of the AWS CICD-toolchain-for-serverless-applications are affected by this vulnerability.
Is there a fix available for this privilege escalation flaw?
Yes, AWS has released version 1.0.11 which addresses the incorrect privilege assignment in the IAM policy.
What access does an attacker need to exploit this vulnerability?
An attacker needs to be a remote authenticated user with push access to the application source repository to exploit the flaw.
