CVE-2026-115413 - AWS API MCP Server OAuth token audience validation bypass
CVE-2026-115413
Summary
Bulletin ID: 2026-094-AWS
Scope: AWS
Content Type: Important (requires attention)
Publication Date: 09/02/2026 13:30 AM PDT
Description:
Amazon Ion-C (ion-c) is the C implementation of the Amazon Ion data serialization format. It is distributed as an open-source library (amazon-ion/ion-c) that applications embed to read and write Ion text and binary data.
We identified CVE-2026-84851, an uncontrolled recursion issue in versions before 1.1.6 that might allow a remote unauthenticated actor to craft Ion data that exhausts the native call stack and crashes the application using the library, resulting in a denial of service.
Impacted versions: < 1.1.6
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Products covered
A separate affected-products list was not included in the collected bulletin.
Remediation
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CVEs in this advisory 1
Update history
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