A malicious extension with the search permission could have installed a new search engine whose favicon referenced a cross-origin URL. The response to this cross-origin request could have been read by the extension, allowing a same-origin policy bypass by the extension, which should not have cross-origin permissions. This cross-origin request was made without cookies, so the sensitive information disclosed by the violation was limited to local-network resources or resources that perform IP-based authentication. This vulnerability affects Firefox < 87.
The product does not properly verify that the source of data or communication is valid.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Firefox | Mozilla | * | 87.0 (excluding) |