Versions of parcel-bundler before 1.10.0 are missing origin validation on the websocket server. This vulnerability allows a remote attacker to steal a developer's source code because the origin of requests to the websocket server that is used for Hot Module Replacement (HMR) are not validated.
Update to version 1.10.0 or later.
{
"cwe_ids": [
"CWE-200"
],
"github_reviewed": true,
"github_reviewed_at": "2020-06-16T20:54:24Z",
"nvd_published_at": null,
"severity": "HIGH"
}