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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-4519 Detail

Description

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().


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  Python Software Foundation
CVSS-B 7.0 HIGH
Vector:  CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2026/03/20/1 CVE
https://github.com/python/cpython/commit/43fe06b96f6a6cf5cfd5bdab20b8649374956866 Python Software Foundation
https://github.com/python/cpython/commit/82a24a4442312bdcfc4c799885e8b3e00990f02b Python Software Foundation
https://github.com/python/cpython/commit/9669a912a0e329c094e992204d6bdb8787024d76 Python Software Foundation
https://github.com/python/cpython/commit/ad4d5ba32af4d80b0dfa2ba9d8203bfb219e60a5 Python Software Foundation
https://github.com/python/cpython/commit/cbba6119391112aba9c5aebf7b94aea447922c48 Python Software Foundation
https://github.com/python/cpython/commit/ceac1efc66516ac387eef2c9a0ce671895b44f03 Python Software Foundation
https://github.com/python/cpython/issues/143930 Python Software Foundation
https://github.com/python/cpython/pull/143931 Python Software Foundation
https://mail.python.org/archives/list/[email protected]/thread/AY5NDSS433JK56Q7Q5IS7B37QFZVVOUS/ Python Software Foundation

Weakness Enumeration

CWE-ID CWE Name Source
CWE-20 Improper Input Validation CISA-ADP  

Change History

6 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-4519
NVD Published Date:
03/20/2026
NVD Last Modified:
03/25/2026
Source:
Python Software Foundation