pyLoad vulnerabilities

In pyLoad prior to version 0.5.0b3.dev100, there is a vulnerability that allows a user with Perms.MODIFY to specify arbitrary directories as download locations for a package through the set_package_data() API function. The lack of sanitization in the '_folder' key enables this action.

In pyLoad prior to version 0.5.0b3.dev100, the set_config_value() API method improperly managed security-sensitive options, allowing authenticated users with SETTINGS permission to enable proxying and route traffic through a host they control.

pyLoad in version 0.5.0b3.dev96 and earlier has an SSRF vulnerability. The fix for CVE-2026-33992 added IP validation, but pycurl automatically follows HTTP redirects and redirect targets are not validated. An authenticated user with ADD permission can bypass the SSRF filter by using a URL that redirects to an internal address.

Vulnerability in pyLoad where the `/web/<path:filename>` route renders Jinja2 templates without authentication. An exception attribute typo leaks internal Jinja2 variable names in HTTP 500 responses.

Vulnerability in pyLoad where the API `rpc` function reads the entire uploaded file into memory without a size limit, potentially exhausting server memory and terminating the process.

In pyLoad prior to 0.5.0b3.dev101, EventManager in src/pyload/core/managers/event_manager.py appends a Client object to the clients list for each unique uuid submitted to the authenticated getEvents API endpoint, but get_events does not invoke the available clean method to remove inactive clients. An authenticated user can repeatedly submit unique UUID values, causing retained client objects and process memory to grow without bound.

In pyLoad prior to 0.5.0b3.dev101, is_global_address in src/pyload/core/utils/web/check.py relies on Python's global-address classification without examining IPv4 destinations embedded in 6to4 or NAT64 IPv6 addresses. A low-privileged user can submit an IPv6 literal through parse_urls to the pre-resolution is_global_host guard, and curl resolves hostnames before the same vulnerable check is applied, permitting connections to embedded loopback, private, CGNAT, or link-local IPv4 addresses.

In pyLoad 0.5.0b3.dev96 and earlier, the parse_urls API function fetches arbitrary URLs server-side without validation. An authenticated user with ADD permission can read internal resources, local files (file://), and use gopher:// and dict:// protocols.

In versions prior to 0.5.0b3.dev91, pyLoad web interface contained insufficient input validation in both the Captcha script endpoint and the Click'N'Load (CNL) Blueprint. This flaw allowed untrusted user input to be processed unsafely, which could be exploited by an attacker to inject arbitrary content into the web UI or manipulate request handling. The vulnerability could lead to client-side code execution (XSS) or other unintended behaviors when a malicious payload is submitted. user-supplied parameters from HTTP requests were not adequately validated or sanitized before being passed into the application logic and response generation. This allowed crafted input to alter the expected execution flow. CNL (Click'N'Load) blueprint exposed unsafe handling of untrusted parameters in HTTP requests. The application did not consistently enforce input validation or encoding, making it possible for an attacker to craft malicious requests. Version 0.5.0b3.dev91 contains a patch for the issue.

pyLoad 0.5.0 is vulnerable to unrestricted file upload, allowing an attacker to upload arbitrary files to the server without proper validation.