Path Traversal in Pyload

CVE-2025-54140

pyLoad is a free and open-source Download Manager written in pure Python. In version 0.5.0b3.dev89, an authenticated path traversal vulnerability exists in the /json/upload endpoint of pyLoad. By manipulating the filename of an uploaded file, an attacker can traverse out of the intended upload directory, allowing them to write arbitrary files to any location on the system accessible to the pyLoad process. This may lead to: Remote Code Execution (RCE), local privilege escalation, system-wide compromise, persistence, and backdoors. This is fixed in version 0.5.0b3.dev90.

Vulnerability class: Path Traversal (Directory Traversal)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.006 (49.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 49.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-54140: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000

Affected products

  • Pyload — versions >= 0.5.0b3.dev89, < 0.5.0b3.dev90

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-54140?
CVE-2025-54140 is a high-severity vulnerability in Pyload, classified under Path Traversal. CVSS score: 7.5/10. Published 2025-07-22.
How severe is CVE-2025-54140?
High severity. CVSS v3 base score is 7.5 out of 10.