What’s Vulnerable › Vulnerabilities

CVE-2026-75936: Memory-amplification denial of service via GZIP decompression bomb in Amazon ion-java

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-18 · updated 2026-10-22
• Weakness: CWE-409

Description

Improper handling of highly compressed data in the GZIP auto-decompression handler in Amazon ion-java before 1.12.0 might allow remote actors to cause a denial of service via a crafted compressed Ion document that expands to an arbitrarily large size upon decompression. To remediate this issue, users should upgrade to version 1.12.0 and configure withGzipDecompressionEnabled(false) and/or set an explicit withMaximumBufferSize() when parsing untrusted input.

Affected products

• Amazon Ion Java: before 1.12.0 — fixed in 1.12.0

How to fix

Upgrade to a fixed version: Amazon Ion Java 1.12.0. Check the vendor advisory for mitigations.

References

• https://aws.amazon.com/security/security-bulletins/2026-083-aws/
• https://github.com/amazon-ion/ion-java/releases/tag/v1.12.0
• https://github.com/amazon-ion/ion-java/security/advisories/GHSA-wj53-jv76-65mc

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