Vulnerability Description
pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev98, the set_session_cookie_secure before_request handler in src/pyload/webui/app/__init__.py reads the X-Forwarded-Proto header from any HTTP request without validating that the request originates from a trusted proxy, then mutates the global Flask configuration SESSION_COOKIE_SECURE on every request. Because pyLoad uses the multi-threaded Cheroot WSGI server (request_queue_size=512), this creates a race condition where an attacker's request can influence the Secure flag on other users' session cookies — either downgrading cookie security behind a TLS proxy or causing a session denial-of-service on plain HTTP deployments. This vulnerability is fixed in 0.5.0b3.dev98.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Pyload-Ng Project | Pyload-Ng | < 0.5.0b3.dev69 |
Related Weaknesses (CWE)
References
- https://github.com/pyload/pyload/security/advisories/GHSA-mp82-fmj6-f22vExploitMitigationVendor Advisory
- https://github.com/pyload/pyload/security/advisories/GHSA-mp82-fmj6-f22vExploitMitigationVendor Advisory
FAQ
What is CVE-2026-40594?
CVE-2026-40594 is a vulnerability with a CVSS score of 4.8 (MEDIUM). pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev98, the set_session_cookie_secure before_request handler in src/pyload/webui/app/__init__.py reads the X-Forwar...
How severe is CVE-2026-40594?
CVE-2026-40594 has been rated MEDIUM with a CVSS base score of 4.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-40594?
Check the references section above for vendor advisories and patch information. Affected products include: Pyload-Ng Project Pyload-Ng.