Unset all possible dash/underscore combinations of REMOTE_USER #1181
Conversation
This file contains 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
While the backend will always see underscores, as dashes are not permitted in environment variables that are used to pass these along, the frontend should always filter all possible notations, as otherwise an attacker could set the "REMOTE-USER" header which gets passed as "REMOTE_USER" unfiltered. Do the same for REMOTE_USER_* to avoid sneaking in groups that the user does not belong to and other user preferences. This however is only a theoretical attack vector once you can't spoof the REMOTE_USER variable anymore.
ekohl
approved these changes
Sep 4, 2024
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Outdated suggestions cannot be applied.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.
While the backend will always see underscores, as dashes are not permitted in environment variables that are used to pass these along, the frontend should always filter all possible notations, as otherwise an attacker could set the "REMOTE-USER" header which gets passed as "REMOTE_USER" unfiltered.
Do the same for REMOTE_USER_* to avoid sneaking in groups that the user does not belong to and other user preferences. This however is only a theoretical attack vector once you can't spoof the REMOTE_USER variable anymore.