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…

PriorityP268critical9.8CVSS 3.1

AVNACLPRNUINSUCHIHAH

EPSS

1.05%

59.9th percentile

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

2 ranges

Vendor	Product	Version range	Fixed in
jugmac00	flask-reuploaded	< 1.5.0	1.5.0
jugmac00	flask-reuploaded	>= 0 < 1.5.0	1.5.0

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