How many CVEs have patched _check_url?

1 published CVEs changed _check_url in python/cpython, in 11 distinct patches totalling 6 changed lines, between 2026 and 2026.

What is the latest CVE that changed _check_url?

CVE-2026-4519 (webbrowser.open() allows leading dashes in URLs), published 2026-03-20, changed lines 157 to 162 of Lib/webbrowser.py.

How does _check_url compare to the rest of python/cpython?

python/cpython has 118 CVEs with a located fix in total; 1 of them changed _check_url.

What do the line numbers refer to?

Line numbers are in the fixed version of the file, as the upstream patch left it. A CVE whose fix was backported to several branches is listed once, with the lines from the upstream commit.

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Patched Functions
Python
Cpython
_check_url

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Patched Functions
Python
Cpython
_check_url

_check_url in python/cpython: Patched by 1 CVEs

python/cpython

Function

_check_url

Name: _check_url in python/cpython: CVE fixes
Creator: RadicalNotion.AI
License: https://creativecommons.org/licenses/by-nc/4.0/

Lib/webbrowser.py

Last patched March 20, 2026

CVEs

That changed this function

Distinct patches

Backports counted once

Lines changed

Added plus removed

2026

Years

By CVE publication date

Overview

_check_url in python/cpython was changed by 1 published CVE fixes in 2026, in 11 distinct patches that added or removed 6 lines in total.

python/cpython has 118 CVEs with a located fix in total, so 1% of them touched this function.

CVEs that patched it

Every published CVE whose fix changed _check_url, newest first, with the lines each fix touched.

On this page

Overview
CVEs that patched it
Other functions in these files
Other hotspots in the repository
FAQ
References

webbrowser.open() allows leading dashes in URLs
CVE-2026-4519 · lines 157–162 · +6 −0
High · CVSS 7.0
EPSS 0.4%2026-03-20

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Other functions in these files

Functions in the same file that CVE fixes also changed.

1openLib/webbrowser.py2 CVEs · 12 patches2026

Other hotspots in the repository

Functions in python/cpython changed by the most CVE fixes.

makelink_with_filter9 CVEs · Lib/tarfile.py _get_filtered_attrs7 CVEs · Lib/tarfile.py extract6 CVEs · Lib/tarfile.py _get_sep5 CVEs · Lib/posixpath.py _readlink_deep5 CVEs · Lib/ntpath.py _get_bothseps5 CVEs · Lib/ntpath.py

All patched functions in python/cpython

Frequently asked questions

Common questions about CVE fixes to _check_url.

How many CVEs have patched _check_url?: 1 published CVEs changed _check_url in python/cpython, in 11 distinct patches totalling 6 changed lines, between 2026 and 2026.
What is the latest CVE that changed _check_url?: CVE-2026-4519 (webbrowser.open() allows leading dashes in URLs), published 2026-03-20, changed lines 157 to 162 of Lib/webbrowser.py.
How does _check_url compare to the rest of python/cpython?: python/cpython has 118 CVEs with a located fix in total; 1 of them changed _check_url.
What do the line numbers refer to?: Line numbers are in the fixed version of the file, as the upstream patch left it. A CVE whose fix was backported to several branches is listed once, with the lines from the upstream commit.

References

Lib/webbrowser.py on GitHub (opens in a new tab)
All patched functions in python/cpython
Patched functions directory

Fix locations are computed by RadicalNotion.AI from the upstream patch diff of each CVE. CVE data is sourced from the CVE Program.

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