Quick answers
- Is CVE-2026-86926 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-86926 being exploited in the wild.
- How severe is CVE-2026-86926?
- High severity, with a CVSS score of 7.8, published 23 September 2026.
- Which products and versions are affected?
- Claris FileMaker Server before 26.0.3.
- Is there a fix for CVE-2026-86926?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-86926 attacked?
- It is attacked with local access, in a web application.
- Am I affected by CVE-2026-86926?
- Check whether you run Claris FileMaker Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A heap buffer overflow exists in the FileMaker Server database engine's block parsing routine when processing .fmp12 files. An attacker can supply a maliciously crafted database file to trigger the overflow, leading to memory corruption and potential arbitrary code execution. The vulnerability is fixed in FileMaker Server 26.0.3.
Affected products
- Claris FileMaker Server before 26.0.3
Timeline
- 2026-09-23: disclosed