Improper input validation in Python
CVE-2026-4519
The webbrowser.open() API would accept leading dashes in the URL which could be handled as command line options for certain web browsers. New behavior rejects leading dashes. Users are recommended to sanitize URLs prior to passing to webbrowser.open().
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.003 (23.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N.
Affected products
- Python — versions 3.15.0
- Python Software Foundation Cpython — versions 3.14.0, 0, 3.13.0
Weakness classification (CWE)
References
- cna@python.org (Patch, patch, Issue Tracking)
- cna@python.org (issue-tracking, Patch, Issue Tracking)
- cna@python.org (vendor-advisory, Vendor Advisory)
- cna@python.org (Patch, patch)
- cna@python.org (Patch, patch)
- cna@python.org (Patch, patch)
- cna@python.org (Patch, patch)
- cna@python.org (Patch, patch)
- cna@python.org (Patch, patch)
- cna@python.org (Patch, patch)
Frequently asked questions
- What is CVE-2026-4519?
- CVE-2026-4519 is a low-severity vulnerability in Python, classified under Improper Input Validation. CVSS score: 3.3/10. Published 2026-03-20.
- How severe is CVE-2026-4519?
- Low severity. CVSS v3 base score is 3.3 out of 10.