CVE-2026-85786: Amazon Ion-Java

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

Improper handling of highly compressed data in Amazon ion-java before 1.12.1 might allow remote attackers to cause a denial of service via a crafted compressed Ion document that expands to an arbitrarily large size upon decompression due to insufficient coverage of the GZIP auto-decompression opt-out introduced for CVE-2026-75936. To remediate this issue, users should upgrade to version 1.12.1.

Affected products

• Amazon Ion-Java: before 1.12.1 (fixed in 1.12.1)

Published 2026-09-04. Last modified 2026-09-08.