Skip to content

Fix: Add message sender validation to service worker and offscreen message handlers #24

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
Copilot wants to merge 2 commits into
base: main
Choose a base branch
from
Draft

Fix: Add message sender validation to service worker and offscreen message handlers #24

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
75002ae
Initial plan
Copilot Mar 12, 2026
4cc5b6a
Fix: Add message sender validation in service worker and offscreen ha…
Copilot Mar 12, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 2 additions & 8 deletions package-lock.json
View file
Open in desktop

Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

18 changes: 17 additions & 1 deletion src/background/service-worker.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -91,7 +91,13 @@ chrome.action.onClicked.addListener(async (tab) => {
/**
* Handle messages from popup
*/
chrome.runtime.onMessage.addListener((message: ExtensionMessage, _sender, sendResponse) => {
chrome.runtime.onMessage.addListener((message: ExtensionMessage, sender, sendResponse) => {
// Reject messages from other extensions or web pages
if (sender.id !== chrome.runtime.id) {
sendResponse({ success: false, error: 'Unauthorized sender' });
return false;
}

console.log('Message received:', message.type, message.payload);

switch (message.type) {
Expand All @@ -108,12 +114,22 @@ chrome.runtime.onMessage.addListener((message: ExtensionMessage, _sender, sendRe
return true; // Keep channel open for async response

case 'UPLOAD_ASSET':
// Only allow from extension pages, not content scripts
if (sender.tab) {
sendResponse({ success: false, error: 'Unauthorized sender' });
return false;
}
handleAssetUpload(message.payload)
.then(() => sendResponse({ success: true }))
.catch((error) => sendResponse({ success: false, error: error.message }));
return true;

case 'START_GOOGLE_AUTH':
// Only allow from extension pages, not content scripts
if (sender.tab) {
sendResponse({ success: false, error: 'Unauthorized sender' });
return false;
}
console.log('Starting Google Auth in background...');
(async () => {
try {
Expand Down
8 changes: 7 additions & 1 deletion src/offscreen/offscreen.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -26,7 +26,13 @@ interface WatermarkPayload {
}

// Listen for messages from service worker
chrome.runtime.onMessage.addListener((message, _sender, sendResponse) => {
chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
// Reject messages from other extensions or web pages
if (sender.id !== chrome.runtime.id) {
sendResponse({ success: false, error: 'Unauthorized sender' });
return false;
}

if (message.type === 'ADD_WATERMARK') {
addWatermark(message.payload)
.then((result) => sendResponse({ success: true, data: result }))
Expand Down