Authenticated file upload via unchecked filename extension
Published Jul 21, 2026 · Updated Jul 21, 2026
Unrestricted file upload in ZS-Admin up to commit b52e14536d59fda11e56e2536a1c32e82a38cead allows remote authenticated users to store dangerous files. LocalFileStrategy copies the original filename extension into a UUID-based name and writes the MultipartFile without an extension, MIME-type, or signature allowlist; WebConfig then exposes the upload directory at /file/**. A valid account with access to the upload endpoint is required, and confirmed impact is limited to arbitrary-extension file storage and retrieval because server-side execution was not demonstrated.
Summary
What happened
Unrestricted file upload in ZS-Admin up to commit b52e14536d59fda11e56e2536a1c32e82a38cead allows remote authenticated users to store dangerous files. LocalFileStrategy copies the original filename extension into a UUID-based name and writes the MultipartFile without an extension, MIME-type, or signature allowlist; WebConfig then exposes the upload directory at /file/**. A valid account with access to the upload endpoint is required, and confirmed impact is limited to arbitrary-extension file storage and retrieval because server-side execution was not demonstrated.
The record
- CVE
- CVE-2026-16451
- Published
- Jul 21, 2026
- Updated
- Jul 21, 2026
- Vendor
- zsadmin2025
- Product
- ZS-Admin
- Classifications
- CWE-434, T1105
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 21, 2026CVE publishedPublication date reported by the CVE source.
- Jul 21, 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=b52e14536d59fda11e56e2536a1c32e82a38cead
What conditions does exploitation require?
What is affected?
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.
Weakness, pattern, technique
Public exploit references
- GitHub issue HTTP proof of conceptproof of concept · demonstrated
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
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo