The HttpRequest object allows to get the HTTP headers from the server's response after sending the request. The problem is that the returned strings are created directly from the data returned by the server and are not correctly encoded for JavaScript. This allows to create internal strings that can be used to access hidden properties of objects.
In the src/libs/zbxembed/browser.c file, the es_browser_ctor method retrieves a heap pointer from the Duktape JavaScript engine. This heap pointer is subsequently utilized by the browser_push_error method in the src/libs/zbxembed/browser_error.c file. A use-after-free bug can occur at this stage if the wd->browser heap pointer is freed by garbage collection.
When the webdriver for the Browser object downloads data from a HTTP server, the data pointer is set to NULL and is allocated only in curl_write_cb when receiving data. If the server's response is an empty document, then wd->data in the code below will remain NULL and an attempt to read from it will result in a crash.
The webdriver for the Browser object expects an error object to be initialized when the webdriver_session_query function fails. But this function can fail for various reasons without an error description and then the wd->error will be NULL and trying to read from it will result in a crash.
When a URL is added to the map element, it is recorded in the database with sequential IDs. Upon adding a new URL, the system retrieves the last sysmapelementurlid value and increments it by one. However, an issue arises when a user manually changes the sysmapelementurlid value by adding sysmapelementurlid + 1. This action prevents others from adding URLs to the map element.