[3.11] gh-143930: Reject leading dashes in webbrowser URLs (GH-143931)#146364
Merged
ambv merged 1 commit intoMar 24, 2026
python:3.11python/cpython:3.11from
tomcruiseqi:backport-82a24a4-3.11tomcruiseqi/cpython:backport-82a24a4-3.11Copy head branch name to clipboard
Merged
[3.11] gh-143930: Reject leading dashes in webbrowser URLs (GH-143931)#146364ambv merged 1 commit intopython:3.11python/cpython:3.11from tomcruiseqi:backport-82a24a4-3.11tomcruiseqi/cpython:backport-82a24a4-3.11Copy head branch name to clipboard
ambv merged 1 commit into
python:3.11python/cpython:3.11from
tomcruiseqi:backport-82a24a4-3.11tomcruiseqi/cpython:backport-82a24a4-3.11Copy head branch name to clipboard
Conversation
(cherry picked from commit 82a24a4)
There was a problem hiding this comment.
Pull request overview
Security hardening for webbrowser to prevent option-injection style issues when URLs are forwarded to external browser commands.
Changes:
- Add URL validation that rejects inputs whose first non-whitespace character is
-. - Invoke this validation across built-in browser controller implementations before launching/dispatching.
- Add a regression test for the new rejection behavior and a Security NEWS entry.
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.
| File | Description |
|---|---|
| Misc/NEWS.d/next/Security/2026-01-16-12-04-49.gh-issue-143930.zYC5x3.rst | Documents the security behavior change for webbrowser.open(). |
| Lib/webbrowser.py | Introduces _check_url() and applies it to multiple controllers before executing browser actions. |
| Lib/test/test_webbrowser.py | Adds a regression test ensuring dash-prefixed inputs are rejected. |
💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.
hroncok
pushed a commit
to fedora-python/cpython
that referenced
this pull request
Mar 26, 2026
Reject leading dashes in webbrowser URLs (pythonGH-143931) (pythonGH-146364) (cherry picked from commit 82a24a4) Co-authored-by: Seth Michael Larson <seth@python.org>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
(cherry picked from commit 82a24a4)