CVE-2026-41133
Session Fixation in pyLoad Allows Privilege Retention Post-Role Change
Publication date: 2026-04-22
Last updated on: 2026-04-27
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| pyload | pyload | to 2026-04-13 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-613 | According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization." |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in pyLoad, a Python-based download manager, in versions up to and including 0.5.0b3.dev97. The issue is that the application caches the user's role and permission information in the session at login and continues to use these cached values for authorization. Even if an administrator changes the user's role or permissions in the database after login, the cached values remain in effect until the user logs out or the session expires.
As a result, a logged-in user can retain old, revoked privileges and continue to perform actions that should no longer be authorized. This is a core authorization and session consistency problem that is not fixed by toggling optional security features.
How can this vulnerability impact me? :
This vulnerability can allow a user who has had their privileges revoked to continue performing privileged actions without proper authorization until they log out or their session expires.
The impact includes unauthorized access to sensitive functions or data, potentially leading to data breaches, unauthorized modifications, or other harmful actions within the application.
Given the CVSS score of 8.8, the vulnerability is considered high severity, indicating significant confidentiality, integrity, and availability impacts.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, the immediate step is to update pyLoad to a version that includes the fix for this issue. The fix is contained in commit e95804fb0d06cbb07d2ba380fc494d9ff89b68c1.
Until the update is applied, it is important to ensure that users log out and their sessions expire to revoke any old cached roles and permissions.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
This vulnerability allows a logged-in user to retain revoked privileges until logout or session expiry, enabling continued privileged actions despite changes in user roles or permissions.
Such unauthorized continued access to elevated privileges can lead to violations of access control requirements mandated by common standards and regulations like GDPR and HIPAA, which require strict control over user permissions and timely revocation of access.
Therefore, this vulnerability may negatively impact compliance by allowing unauthorized access to sensitive data or functions beyond the intended permissions.