fix: add Host header validation to prevent DNS rebinding attacks#1287
Merged
cristipufu merged 1 commit intomainfrom Feb 11, 2026
Merged
fix: add Host header validation to prevent DNS rebinding attacks#1287cristipufu merged 1 commit intomainfrom
cristipufu merged 1 commit intomainfrom
Conversation
github-actions
bot
added
test:uipath-langchain
cristipufu
force-pushed
the
fix/dns-rebinding-host-validation
branch
from
ef54f06 to
0e7fecc
Compare
cristipufu
force-pushed
the
fix/dns-rebinding-host-validation
branch
2 times, most recently
from
ddf3430 to
fc3cafe
Compare
The server binds to 127.0.0.1 but did not validate the Host header, making it vulnerable to DNS rebinding attacks (CVSS 6.5). An attacker could use a domain that resolves to 127.0.0.1 to bypass same-origin policy and execute commands on the local server. Add aiohttp middleware that rejects requests where the Host header is not 127.0.0.1, localhost, or [::1]. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
cristipufu
force-pushed
the
fix/dns-rebinding-host-validation
branch
from
fc3cafe to
1997edb
Compare
cotovanu-cristian
approved these changes
Feb 11, 2026
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Summary
Hostheader on all incoming requests to the CLI server127.0.0.1,localhost, or[::1]with a 403 Forbidden response127.0.0.1could bypass same-origin policy and execute arbitrary commands on the local serverTest plan
test_rejects_invalid_host_header— verifies attacker-controlled domains get 403test_allows_localhost_host_header— verifies localhost variants are accepted🤖 Generated with Claude Code