CVE-2026-27641

Flask-Reuploaded provides file uploads for Flask. A critical path traversal and extension bypass vulnerability in versions prior to 1.5.0 allows remote attackers to achieve arbitrary file write and remote code execution through Server-Side Template Injection (SSTI). Flask-Reuploaded has been patched in version 1.5.0. Some workarounds are available. Do not pass user input to the `name` parameter, use auto-generated filenames only, and implement strict input validation if `name` must be used.

Affected products

Flask-Reuploaded

jugmac00 Flask-reuploaded

< 1.5.0

Fix

Available

CVSS 3.1

9.8 CRITICAL

EPSS

1.2% (66th percentile)

Weakness

CWE-22, CWE-1336

NVD status

Analyzed

Published

2026-02-25