RCE in Pyload

CVE-2025-53890

pyload is an open-source Download Manager written in pure Python. An unsafe JavaScript evaluation vulnerability in pyLoad’s CAPTCHA processing code allows unauthenticated remote attackers to execute arbitrary code in the client browser and potentially the backend server. Exploitation requires no user interaction or authentication and can result in session hijacking, credential theft, and full system remote code execution. Commit 909e5c97885237530d1264cfceb5555870eb9546, the patch for the issue, is included in version 0.5.0b3.dev89.

Vulnerability class: RCE (Remote Code Execution)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.012 (66.0th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 66th percentile — 66.0% 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-2025-53890: held from 0.012 to 0.012.

EPSS over last 30 days · oldest: 0.012 · newest: 0.012 · change: +0.000

Affected products

  • Pyload — versions < 0.5.0b3.dev89

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-53890?
CVE-2025-53890 is a critical-severity vulnerability in Pyload, classified under Code Injection. CVSS score: 9.8/10. Published 2025-07-15.
How severe is CVE-2025-53890?
Critical severity. CVSS v3 base score is 9.8 out of 10.