CVE-2026-40594

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 v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/pyload/pyload/security/advisories/GHSA-mp82-fmj6-f22v	Exploit Mitigation Vendor Advisory
https://github.com/pyload/pyload/security/advisories/GHSA-mp82-fmj6-f22v	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:pyload-ng_project:pyload-ng:*:*:*:*:*:python:*:*

History

No history.

Information

Published : 2026-04-21 18:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40594

Mitre link : CVE-2026-40594

CVE.ORG link : CVE-2026-40594

JSON object : View

Products Affected

pyload-ng_project

pyload-ng

CWE

CWE-346

Origin Validation Error

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