If an HTTP authentication prompt is triggered by a background network request from a page or extension, it is displayed over the currently loaded foreground page. Although the prompt contains the real domain making the request, this can result in user confusion about the originating site of the authentication request and may cause users to mistakenly send private credential information to a third party site. This vulnerability affects Firefox < 58.

If an existing cookie is changed to be "HttpOnly" while a document is open, the original value remains accessible through script until that document is closed. Network requests correctly use the changed HttpOnly cookie. This vulnerability affects Firefox < 58.

The "browser.identity.launchWebAuthFlow" function of WebExtensions is only allowed to load content over "https:" but this requirement was not properly enforced. This can potentially allow privileged pages to be loaded by the extension. This vulnerability affects Firefox < 58.

Development Tools panels of an extension are required to load URLs for the panels as relative URLs from the extension manifest file but this requirement was not enforced in all instances. This could allow the development tools panel for the extension to load a URL that it should not be able to access, including potentially privileged pages. This vulnerability affects Firefox < 58.

When the text of a specially formatted URL is dragged to the addressbar from page content, the displayed URL can be spoofed to show a different site than the one loaded. This allows for phishing attacks where a malicious page can spoof the identify of another site. This vulnerability affects Firefox < 58.

If cursor visibility is toggled by script using from 'none' to an image and back through script, the cursor will be rendered temporarily invisible within Firefox. Note: This vulnerability only affects OS X. Other operating systems are not affected. This vulnerability affects Firefox < 58.

An audio capture session can started under an incorrect origin from the site making the capture request. Users are still prompted to allow the request but the prompt can display the wrong origin, leading to user confusion about which site is making the request to capture an audio stream. This vulnerability affects Firefox < 58.

A Blob URL can violate origin attribute segregation, allowing it to be accessed from a private browsing tab and for data to be passed between the private browsing tab and a normal tab. This could allow for the leaking of private information specific to the private browsing context. This issue is mitigated by the requirement that the user enter the Blob URL manually in order for the access violation to occur. This vulnerability affects Firefox < 58.

The printing process can bypass local access protections to read files available through symlinks, bypassing local file restrictions. The printing process requires files in a specific format so arbitrary data cannot be read but it is possible that some local file information could be exposed. This vulnerability affects Firefox < 58.

Style editor traffic in the Developer Tools can be routed through a service worker hosted on a third party website if a user selects error links when these tools are open. This can allow style editor information used within Developer Tools to leak cross-origin. This vulnerability affects Firefox < 58.

WebExtensions can bypass user prompts to first save and then open an arbitrarily downloaded file. This can result in an executable file running with local user privileges without explicit user consent. This vulnerability affects Firefox < 58.

A use-after-free vulnerability can occur during font face manipulation when a font face is freed while still in use, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

A use-after-free vulnerability can occur during mouse event handling due to issues with multiprocess support. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

A use-after-free vulnerability can occur when manipulating HTML media elements with media streams, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

A use-after-free vulnerability can occur when manipulating floating "first-letter" style elements, resulting in a potentially exploitable crash. This vulnerability affects Firefox < 58.

A use-after-free vulnerability can occur when arguments passed to the "IsPotentiallyScrollable" function are freed while still in use by scripts. This results in a potentially exploitable crash. This vulnerability affects Firefox < 58.

A use-after-free vulnerability can occur when the widget listener is holding strong references to browser objects that have previously been freed, resulting in a potentially exploitable crash when these references are used. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

A use-after-free vulnerability can occur when form input elements, focus, and selections are manipulated by script content. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

A use-after-free vulnerability can occur during XSL transformations when the source document for the transformation is manipulated by script content during the transformation. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.

An integer overflow vulnerability in the Skia library when allocating memory for edge builders on some systems with at least 8 GB of RAM. This results in the use of uninitialized memory, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 52.6, Firefox ESR < 52.6, and Firefox < 58.