Flask-Reuploaded vulnerable to Remote Code Execution via Server-Side Template InjectionGHSA-65mp-fq8v-56jr
CRITICALFix: jugmac00/flask-reuploaded#180GHSA-65mp-fq8v-56jr is a critical-severity (CVSS 9.8) CWE-1336 vulnerability in flask-reuploaded. A fix is available for flask-reuploaded — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-65mp-fq8v-56jr.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
flask-reuploadedReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Impact
A critical path traversal and extension bypass vulnerability in Flask-Reuploaded allows remote attackers to achieve arbitrary file write and remote code execution through Server-Side Template Injection (SSTI).
Patches
Flask-Reuploaded has been patched in version 1.5.0
Workarounds
- Do not pass user input to the
nameparameter - Use auto-generated filenames only
- Implement strict input validation if
namemust be used
from werkzeug.utils import secure_filename
import os
# Sanitize user input before passing to save()
safe_name = secure_filename(request.form.get('custom_name'))
# Remove path separators
safe_name = os.path.basename(safe_name)
# Validate extension matches policy
if not photos.extension_allowed(photos.get_extension(safe_name)):
abort(400)
filename = photos.save(file, name=safe_name)
Resources
The fix is documented in the pull request, see https://github.com/jugmac00/flask-reuploaded/pull/180.
A proper write-up was created by the reporter of the vulnerability, Jaron Cabral (https://www.linkedin.com/in/jaron-cabral-751994357/), but is not yet available as of time of this publication.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | flask-reuploaded | all versions | 1.5.0pip install --upgrade 'flask-reuploaded==1.5.0' |
Affected Products
flask-reuploadedjugmac00Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for flask-reuploaded, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update flask-reuploaded to 1.5.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-65mp-fq8v-56jr is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.
Frequently Asked Questions
Is GHSA-65mp-fq8v-56jr in your dependencies?
Find it across PyPI, including transitive dependencies.