Authenticated code execution via MIME-spoofed avatar upload
Published Feb 23, 2026 · Updated Feb 23, 2026
Unrestricted file upload in FastapiAdmin 2.2.0 and earlier allows remote authenticated users to execute code through the avatar endpoint. UploadUtil.check_file_extension derives an allowed extension from the client-controlled Content-Type header, then upload_file writes the supplied bytes without verifying that content. Any authenticated user can store a disguised file; code execution additionally requires chaining the upload with the scheduled-task APIs.
Summary
What happened
Unrestricted file upload in FastapiAdmin 2.2.0 and earlier allows remote authenticated users to execute code through the avatar endpoint. UploadUtil.check_file_extension derives an allowed extension from the client-controlled Content-Type header, then upload_file writes the supplied bytes without verifying that content. Any authenticated user can store a disguised file; code execution additionally requires chaining the upload with the scheduled-task APIs.
The record
- CVE
- CVE-2026-2979
- Published
- Feb 23, 2026
- Updated
- Feb 23, 2026
- Vendor
- FastapiAdmin
- Product
- FastapiAdmin
- Classifications
- CWE-284, CWE-434, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 23, 2026CVE publishedPublication date reported by the CVE source.
- Feb 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=2.0
- Affected versionversion=2.1
- Affected versionversion=2.2.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- FastapiAdmin unrestricted avatar-upload proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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