SVG loaded through "<img>" tags can use "<meta>" tags within the SVG data to set cookies for that page. This vulnerability affects Firefox < 57.

The "pingsender" executable used by the Firefox Health Report dynamically loads a system copy of libcurl, which an attacker could replace. This allows for privilege escalation as the replaced libcurl code will run with Firefox's privileges. Note: This attack requires an attacker have local system access and only affects OS X and Linux. Windows systems are not affected. This vulnerability affects Firefox < 57.

Mixed content blocking of insecure (HTTP) sub-resources in a secure (HTTPS) document was not correctly applied for resources that redirect from HTTPS to HTTP, allowing content that should be blocked, such as scripts, to be loaded on a page. This vulnerability affects Firefox < 57.

A "data:" URL loaded in a new tab did not inherit the Content Security Policy (CSP) of the original page, allowing for bypasses of the policy including the execution of JavaScript. In prior versions when "data:" documents also inherited the context of the original page this would allow for potential cross-site scripting (XSS) attacks. This vulnerability affects Firefox < 57.

Some Arabic and Indic vowel marker characters can be combined with Latin characters in a domain name to eclipse the non-Latin character with some font sets on the addressbar. The non-Latin character will not be visible to most viewers. This allows for domain spoofing attacks because these combined domain names do not display as punycode. This vulnerability affects Firefox < 57.

The combined, single character, version of the letter 'i' with any of the potential accents in unicode, such as acute or grave, can be spoofed in the addressbar by the dotless version of 'i' followed by the same accent as a second character with most font sets. This allows for domain spoofing attacks because these combined domain names do not display as punycode. This vulnerability affects Firefox < 57.

A vulnerability where the security wrapper does not deny access to some exposed properties using the deprecated "_exposedProps_" mechanism on proxy objects. These properties should be explicitly unavailable to proxy objects. This vulnerability affects Firefox < 57.

Mozilla: From address with encoded null character is cut off in message header display

It is possible to spoof the sender's email address and display an arbitrary sender address to the email recipient. The real sender's address is not displayed if preceded by a null character in the display string. This vulnerability affects Thunderbird < 52.5.2.

Memory safety bugs were reported in Firefox 56. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 57.

The AES-GCM implementation in WebCrypto API accepts 0-length IV when it should require a length of 1 according to the NIST Special Publication 800-38D specification. This might allow for the authentication key to be determined in some instances. This vulnerability affects Firefox < 56.

A vulnerability where WebExtensions can download and attempt to open a file of some non-executable file types. This can be triggered without specific user interaction for the file download and open actions. This could be used to trigger known vulnerabilities in the programs that handle those document types. This vulnerability affects Firefox < 56.

The "instanceof" operator can bypass the Xray wrapper mechanism. When called on web content from the browser itself or an extension the web content can provide its own result for that operator, possibly tricking the browser or extension into mishandling the element. This vulnerability affects Firefox < 56.

A spoofing vulnerability can occur when a page switches to fullscreen mode without user notification, allowing a fake address bar to be displayed. This allows an attacker to spoof which page is actually loaded and in use. Note: This attack only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 56.

WebExtensions could use popups and panels in the extension UI to load an "about:" privileged URL, violating security checks that disallow this behavior. This vulnerability affects Firefox < 56.

On pages containing an iframe, the "data:" protocol can be used to create a modal dialog through Javascript that will have an arbitrary domains as the dialog's location, spoofing of the origin of the modal dialog from the user view. Note: This attack only affects installations with e10 multiprocess turned off. Installations with e10s turned on do not support the modal dialog functionality. This vulnerability affects Firefox < 56.

Inside the JavaScript parser, a cast of an integer to a narrower type can result in data read from outside the buffer being parsed. This usually results in a non-exploitable crash, but can leak a limited amount of information from memory if it matches JavaScript identifier syntax. This vulnerability affects Firefox < 56.

If web content on a page is dragged onto portions of the browser UI, such as the tab bar, links can be opened that otherwise would not be allowed to open. This can allow malicious web content to open a locally stored file through "file:" URLs. This vulnerability affects Firefox < 56.

Memory safety bugs were reported in Firefox 55. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 56.

Mozilla: CSP information leak with frame-ancestors containing paths (MFSA 2017-18)

A content security policy (CSP) "frame-ancestors" directive containing origins with paths allows for comparisons against those paths instead of the origin. This results in a cross-origin information leak of this path information. This vulnerability affects Firefox < 55.

Mozilla: Use-after-free in layer manager with SVG (MFSA 2017-18)

A use-after-free vulnerability can occur when the layer manager is freed too early when rendering specific SVG content, resulting in a potentially exploitable crash. This vulnerability affects Firefox < 55.