CVE-2026-115413 - AWS API MCP Server OAuth token audience validation bypass
CVE-2026-115413
Summary
Bulletin ID: 2026-100-AWS
Scope: AWS
Content Type: Important (requires attention)
Publication Date: 09/04/2026 12:30 PM PDT
Description:
ion-java is a Java library that implements the Amazon Ion data format specification. We identified CVE-2026-85786, memory-amplification denial of service via highly compressed data expansion. ion-java 1.12.0 added a GZIP auto-decompression opt-out for CVE-2026-75936, but the implementation of the opt-out in 1.12.0 was insufficient to address the issue.
Impacted versions: < 1.12.1
Please refer to the article below for the most up-to-date and complete information related to this AWS Security Bulletin.
Products covered
A separate affected-products list was not included in the collected bulletin.
Remediation
Separate remediation guidance was not included in the collected bulletin.
CVEs in this advisory 2
Update history
What changed in later vendor updates
SecurityAlert records field-level changes from the point we begin following a bulletin. Earlier vendor changes may not have a field-by-field record.
- The vendor changed the advisory's last-updated date.
- The vendor changed the advisory's last-updated date.
- The vendor changed the advisory's last-updated date.
Updates
- Added to SecurityAlert
We collected the advisory from the official source.
- Published by AWS
The publication date reported by the vendor.
- Confirmed at the source
Our collector saw this advisory during a later source check.