A method securely scans a second web page linked to a first web page being displayed by a browser. The method identifies a target link to a second web page from one or more links contained within a first web page. Prior to receiving a user selection of the target link, the method prefetches content from the second web page and loads the prefetched content from the second web page into a safe cache before receiving the user selection of the target link. The method scans the prefetched content from the second web page for a security threat, within the safe cache, wherein the safe cache is configured to prevent the prefetched content from altering a memory location or storage location external to the safe cache. In response to identifying a security threat within the prefetched content, the method displays a warning to the user.