CVE-2026-64609 Apache Fory, Apache Fory: Out-of-Bounds Read via sun.misc.Unsafe in zero-copy java deserialization

Critical 9.1 Published 21 Jul 2026 Updated 21 Jul 2026

An out-of-bounds read in Apache Fory's zero-copy deserialization allows attackers to read memory or cause crashes when the opt-in feature is enabled.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-64609?

CVE-2026-64609 is a critical memory corruption vulnerability in Apache Fory, published on 21 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Out-of-bounds read via sun.misc.Unsafe in Apache Fory. When out-of-band zero-copy deserialization is used, readAlignedVarUint() can read beyond the bounds of the underlying buffer. Out-of-band zero-copy deserialization is an opt-in feature; applications that do not use it are not affected.

This issue affects Apache Fory (formerly Apache Fury): from 0.5.0 before 1.4.0. Versions before 0.11.0 were published under the Maven coordinates org.apache.fury:fury-core.

Users are recommended to upgrade to version 1.4.0, which fixes the issue.

Weakness: CWE-125

Which versions are affected by CVE-2026-64609?

It affects 1 product.

Products include Apache Fory.

How do I fix CVE-2026-64609?

No fix has been published for CVE-2026-64609 yet. Limit exposure of the affected software until one is available.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-64609 being exploited?

There is no known exploitation of CVE-2026-64609 in the wild and no public exploit code.

Sources

Also known as GHSA-8w3v-jcfp-ffw5.