CVE-2026-27641 | Flask-Reuploaded provides file uploads for Flask. A critical… | CVSS 9.8 CRITICAL

Description

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.

Metadata

CVE ID: CVE-2026-27641
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-02-20 22:02 UTC
Published: 2026-02-25 03:54 UTC
Last updated: 2026-02-25 21:12 UTC
Primary CWE: CWE-1336
CWE-1336: Improper Neutralization of Special Elements Used i…
Vendor / Product: jugmac00 / flask-reuploaded
Sources: cve.org · NVD

Severity & Metrics

9.8 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC — CISA Coordinator

Exploitation: none
Automatable: yes
Tech. Impact: total

Affected products (1)

Vendor	Product	Platform	Versions
jugmac00	flask-reuploaded	—	< 1.5.0

Weakness (CWE)

CWE	Source	Description
CWE-1336	cna	CWE-1336: Improper Neutralization of Special Elements Used in a Template Engine

CVSS scores (1)

Score	Severity	Version	Source	Vector
9.8	CRITICAL	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References (3)

https://github.com/jugmac00/flask-reuploaded/security/advisories/GHSA-65mp-fq8v-56jr https://github.com/jugmac00/flask-reuploaded/security/advisories/GHSA-65mp-fq8v-56jr
https://github.com/jugmac00/flask-reuploaded/pull/180 https://github.com/jugmac00/flask-reuploaded/pull/180
https://github.com/jugmac00/flask-reuploaded/commit/d64c6b2f71cb73734fc38baa0e3e156926361288 https://github.com/jugmac00/flask-reuploaded/commit/d64c6b2f71cb73734fc38baa0e3e156926361288