VulnerabilityAnalyzed

CVE-2026-27641

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).

CRITICAL 9.8EPSS 1.20%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.20%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1: 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 1.20% probability · 66th percentile
CISA KEV: Not listed
Weakness: CWE-1336, CWE-22
Affected: jugmac00/flask-reuploaded
Source: security-advisories@github.com

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

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.