Process-memory disclosure via thumbnail buffer over-read
Published Sep 23, 2026 · Updated Sep 23, 2026
Out-of-bounds read in FileMaker Server for Linux before 26.0.3 allows remote authenticated users to disclose process memory via image upload. The ImageMagick thumbnail generator reads beyond allocated memory while processing a crafted image stored in a container field. Exploitation requires access to upload that image and invoke thumbnail generation through FileMaker WebDirect; the reported consequence is adjacent heap-memory disclosure.
Summary
What happened
Out-of-bounds read in FileMaker Server for Linux before 26.0.3 allows remote authenticated users to disclose process memory via image upload. The ImageMagick thumbnail generator reads beyond allocated memory while processing a crafted image stored in a container field. Exploitation requires access to upload that image and invoke thumbnail generation through FileMaker WebDirect; the reported consequence is adjacent heap-memory disclosure.
The record
- CVE
- CVE-2026-86930
- Published
- Sep 23, 2026
- Updated
- Sep 23, 2026
- Vendor
- Claris
- Product
- FileMaker Server
- Classifications
- T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 23, 2026CVE publishedPublication date reported by the CVE source.
- Sep 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <26.0.3
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Get started to see how Hinoki identifies affected software and validates exploitability in your environment.
Get started