CVE-2026-86926 Memory corruption in FileMaker Server

High 7.8 Published 23 Sep 2026 Updated 24 Sep 2026

A heap buffer overflow in FileMaker Server allows arbitrary code execution via a malicious database file, requiring an upgrade to the latest version.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2026-86926?

CVE-2026-86926 is a high-severity memory corruption vulnerability in Claris FileMaker Server, published on 23 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

A heap buffer overflow vulnerability in the FileMaker Server database engine block parsing routine allowed a maliciously crafted .fmp12 database file to cause memory corruption, potentially leading to arbitrary code execution. This vulnerability is addressed in FileMaker Server version 26.0.3.

Weakness: CWE-122

Which versions are affected by CVE-2026-86926?

It affects 1 product.

Products include Claris Filemaker Server.

How do I fix CVE-2026-86926?

No fix has been published for CVE-2026-86926 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-2026-86926 being exploited?

There is no known exploitation of CVE-2026-86926 in the wild and no public exploit code.

Sources

Also known as GHSA-9vrp-wjh8-mfg5.