CVE-2026-27641

Name: CVE-2026-27641
Creator: NVD / NIST
Published: 2026-02-25T04:16:04.62+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 1.05%

Last modified Jun 17, 2026

CVE-2026-27641 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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). EPSS estimates a 1.05% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

9.8/10

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

EPSS Probability

1.05%

59.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Jugmac00	Flask-Reuploaded	< 1.5.0

References

https://github.com/jugmac00/flask-reuploaded/commit/d64c6b2f71cb73734fc38baa0e3e156926361288Patch
https://github.com/jugmac00/flask-reuploaded/pull/180Issue Tracking, Patch
https://github.com/jugmac00/flask-reuploaded/security/advisories/GHSA-65mp-fq8v-56jrExploit, Vendor Advisory

Timeline

Published: Feb 25, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-27641?

How severe is CVE-2026-27641?

CVE-2026-27641 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 1.05% probability of exploitation in the next 30 days.

How do I fix CVE-2026-27641?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-27641?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST