Executive brief
pyLoad is an open-source download manager used to automate file downloads. A security flaw allows an authenticated user to trick the application into making requests to internal network addresses that should be restricted. This could allow an attacker to access sensitive internal data, such as cloud metadata or private network services, potentially leading to the exposure of credentials or configuration details.
Technical details
A Server-Side Request Forgery (SSRF) vulnerability exists in pyLoad's parse_urls API due to an incomplete fix for a previous vulnerability. While the application validates the initial URL hostname using is_global_host(), it fails to apply private IP restrictions to subsequent redirects handled by HTTPRequest. An authenticated attacker with 'ADD' permissions can provide a URL to a malicious server that returns a 302 redirect to a private IP (e.g., 127.0.0.1 or 169.254.169.254). Because HTTPRequest defaults to allow_private_ip = True, the internal request is executed. This allows attackers to probe internal services or leak cloud metadata. The issue is fixed in version 0.5.0b3.dev100.
Affected products
- pyLoad pyload-ng <= 0.5.0b3.dev87
Timeline
- 2026-05-15: advisory: GitHub Security Advisory published
- 2026-05-28: disclosed: CVE published to NVD