CVE-2026-86934 Auth bypass in FileMaker Server

Critical 9.1 Published 23 Sep 2026 Updated 24 Sep 2026

Attackers can bypass disabled XML Web Publishing settings via extended privilege headers, gaining unauthorized access to the interface.

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-2026-86934?

CVE-2026-86934 is a critical authentication bypass vulnerability in Claris FileMaker Server, published on 23 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An authorization bypass vulnerability in the FileMaker Server Web Publishing Engine allowed requests containing an extended privilege header to bypass the disabled Custom Web Publishing with XML setting and access the XML Web Publishing interface. This vulnerability is addressed in FileMaker Server version 26.0.3.

Weakness: CWE-639

Which versions are affected by CVE-2026-86934?

It affects 1 product.

Products include Claris Filemaker Server.

How do I fix CVE-2026-86934?

No fix has been published for CVE-2026-86934 yet. Limit exposure of the affected software until one is available.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-86934 being exploited?

There is no known exploitation of CVE-2026-86934 in the wild and no public exploit code.

Sources

Also known as GHSA-wwj7-3493-4j3w.