The HTTP Alternative Services feature in Mozilla Firefox before 37.0.1 allows man-in-the-middle attackers to bypass an intended X.509 certificate-verification step for an SSL server by specifying that server in the uri-host field of an Alt-Svc HTTP/2 response header.

When arbitrary text is sent over an FTP connection and a page reload is initiated, it is possible to create a modal alert message with this text as the content. This could potentially be used for social engineering attacks. This vulnerability affects Firefox < 66.

Mozilla Firefox before 37.0 on OS X does not ensure that the cursor is visible, which allows remote attackers to conduct clickjacking attacks via a Flash object in conjunction with DIV elements associated with layered presentation, and crafted JavaScript code that interacts with an IMG element.

The SELECT element implementation in Mozilla Firefox before 25.0, Firefox ESR 24.x before 24.1, Thunderbird before 24.1, and SeaMonkey before 2.22 does not properly restrict the nature or placement of HTML within a dropdown menu, which allows remote attackers to spoof the address bar or conduct clickjacking attacks via vectors that trigger navigation off of a page containing this element.

CRLF injection vulnerability in the Digest Authentication support for Mozilla Firefox before 2.0.0.8 and SeaMonkey before 1.1.5 allows remote attackers to conduct HTTP request splitting attacks via LF (%0a) bytes in the username attribute.

The cert_TestHostName function in lib/certdb/certdb.c in the certificate-checking implementation in Mozilla Network Security Services (NSS) before 3.16 accepts a wildcard character that is embedded in an internationalized domain name's U-label, which might allow man-in-the-middle attackers to spoof SSL servers via a crafted certificate.

By downloading a file with the .fileloc extension, a semi-privileged extension could launch an arbitrary application on the user's computer. The attacker is restricted as they are unable to download non-quarantined files or supply command line arguments to the application, limiting the impact. Note: this issue only occurs on Mac OSX. Other operating systems are unaffected. This vulnerability affects Thunderbird < 68.5, Firefox < 73, and Firefox < ESR68.5.

Mozilla Firefox before 16.0, Firefox ESR 10.x before 10.0.8, Thunderbird before 16.0, Thunderbird ESR 10.x before 10.0.8, and SeaMonkey before 2.13 do not properly restrict calls to DOMWindowUtils (aka nsDOMWindowUtils) methods, which allows remote attackers to bypass intended access restrictions via crafted JavaScript code.

Mozilla Firefox before 48.0 on Android allows remote attackers to spoof the address bar via left-to-right characters in conjunction with a right-to-left character set.

Mozilla Firefox before 44.0 allows user-assisted remote attackers to spoof a trailing substring in the address bar by leveraging a user's paste of a (1) wyciwyg: URI or (2) resource: URI.

Mozilla Firefox 4.x through 13.0, Firefox ESR 10.x before 10.0.6, Thunderbird 5.0 through 13.0, Thunderbird ESR 10.x before 10.0.6, and SeaMonkey before 2.11 do not properly handle duplicate values in X-Frame-Options headers, which makes it easier for remote attackers to conduct clickjacking attacks via a FRAME element referencing a web site that produces these duplicate values.

If manipulated hyperlinked text with "chrome:" URL contained in it is dragged and dropped on the "home" icon, the home page can be reset to include a normally-unlinkable chrome page as one of the home page tabs. This vulnerability affects Firefox < 60.

The JSON Viewer displays clickable hyperlinks for strings that are parseable as URLs, including "javascript:" links. If a JSON file contains malicious JavaScript script embedded as "javascript:" links, users may be tricked into clicking and running this code in the context of the JSON Viewer. This can allow for the theft of cookies and authorization tokens which are accessible to that context. This vulnerability affects Firefox < 60.

The web console and JavaScript debugger do not sanitize all output that can be hyperlinked. Both will display "chrome:" links as active, clickable hyperlinks in their output. Web sites should not be able to directly link to internal chrome pages. Additionally, the JavaScript debugger will display "javascript:" links, which users could be tricked into clicking by malicious sites. This vulnerability affects Firefox < 60.

It is possible to spoof the filename of an attachment and display an arbitrary attachment name. This could lead to a user opening a remote attachment which is a different file type than expected. This vulnerability affects Thunderbird ESR < 52.8 and Thunderbird < 52.8.

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.

A mechanism where when a new tab is loaded through JavaScript events, if fullscreen mode is then entered, the addressbar will not be rendered. This would allow a malicious site to displayed a spoofed addressbar, showing the location of an arbitrary website instead of the one loaded. Note: this issue only affects Firefox for Android. Desktop Firefox is unaffected. This vulnerability affects Firefox < 54.

A "javascript:" url loaded by a malicious page can obfuscate its location by blanking the URL displayed in the addressbar, allowing for an attacker to spoof an existing page without the malicious page's address being displayed correctly. This vulnerability affects Firefox < 52.

Malicious sites can display a spoofed location bar on a subsequently loaded page when the existing location bar on the new page is scrolled out of view if navigations between pages can be timed correctly. Note: This issue only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 51.

An issue where a "<select>" dropdown menu can be used to cover location bar content, resulting in potential spoofing attacks. This attack requires e10s to be enabled in order to function. This vulnerability affects Firefox < 50.

The JSSubScriptLoader in Mozilla Firefox 4.x through 6 and SeaMonkey before 2.4 does not properly handle XPCNativeWrappers during calls to the loadSubScript method in an add-on, which makes it easier for remote attackers to gain privileges via a crafted web site that leverages certain unwrapping behavior.

A mechanism to spoof the addressbar through the user interaction on the addressbar and the "onblur" event. The event could be used by script to affect text display to make the loaded site appear to be different from the one actually loaded within the addressbar. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 52.1, and Firefox < 53.

The X.509 certificate validation functionality in Mozilla Firefox 4.0.x through 4.0.1 does not properly implement single-session security exceptions, which might make it easier for user-assisted remote attackers to spoof an SSL server via an untrusted certificate that triggers potentially unwanted local caching of documents from that server.

The NS_SecurityCompareURIs function in netwerk/base/public/nsNetUtil.h in Mozilla Firefox before 3.5.16 and 3.6.x before 3.6.13, and SeaMonkey before 2.0.11, does not properly handle (1) about:neterror and (2) about:certerror pages, which allows remote attackers to spoof the location bar via a crafted web site.

intl/uconv/util/nsUnicodeDecodeHelper.cpp in Mozilla Firefox before 3.6.7 and Thunderbird before 3.1.1 inserts a U+FFFD sequence into text in certain circumstances involving undefined positions, which might make it easier for remote attackers to conduct cross-site scripting (XSS) attacks via crafted 8-bit text.

The XMLDocument::load function in Mozilla Firefox before 3.5.9 and 3.6.x before 3.6.2, Thunderbird before 3.0.4, and SeaMonkey before 2.0.4 does not perform the expected nsIContentPolicy checks during loading of content by XML documents, which allows attackers to bypass intended access restrictions via crafted content.

Visual truncation vulnerability in netwerk/dns/src/nsIDNService.cpp in Mozilla Firefox before 3.0.11 and SeaMonkey before 1.1.17 allows remote attackers to spoof the location bar via an IDN with invalid Unicode characters that are displayed as whitespace, as demonstrated by the \u115A through \u115E characters.

Mozilla Firefox 3.x before 3.0.5 and 2.x before 2.0.0.19, Thunderbird 2.x before 2.0.0.19, and SeaMonkey 1.x before 1.1.14 does not properly parse URLs with leading whitespace or control characters, which might allow remote attackers to misrepresent URLs and simplify phishing attacks.

Mozilla Firefox before 2.0.0.12 and SeaMonkey before 1.1.8 allows user-assisted remote attackers to trick the user into uploading arbitrary files via label tags that shift focus to a file input field, aka "focus spoofing."

Malicious sites can display a spoofed addressbar on a page when the existing location bar on the new page is scrolled out of view if an HTML editable page element is user selected. Note: This attack only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 53.

A mechanism to inject static HTML into the RSS reader preview page due to a failure to escape characters sent as URL parameters for a feed's "TITLE" element. This vulnerability allows for spoofing but no scripted content can be run. This vulnerability affects Firefox < 53.

A mechanism where disruption of the loading of a new web page can cause the previous page's favicon and SSL indicator to not be reset when the new page is loaded. Note: this issue only affects Firefox for Android. Desktop Firefox is unaffected. This vulnerability affects Firefox < 50.

Mozilla Firefox before 48.0 allows remote attackers to spoof the location bar via crafted characters in the media type of a data: URL.

When "%2F" was present in a manifest URL, Firefox's AppCache behavior may have become confused and allowed a manifest to be served from a subdirectory. This could cause the appcache to be used to service requests for the top level directory. This vulnerability affects Firefox < 78.

When browsing a document hosted on an IP address, an attacker could insert certain characters to flip domain and path information in the address bar. This vulnerability affects Firefox < 77.

The "Forget about this site" feature in the History pane is intended to remove all saved user data that indicates a user has visited a site. This includes removing any HTTP Strict Transport Security (HSTS) settings received from sites that use it. Due to a bug, sites on the pre-load list also have their HSTS setting removed. On the next visit to that site if the user specifies an http: URL rather than secure https: they will not be protected by the pre-loaded HSTS setting. After that visit the site's HSTS setting will be restored. This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.

Mozilla Firefox before 37.0 does not require an HTTPS session for lightweight theme add-on installations, which allows man-in-the-middle attackers to bypass an intended user-confirmation requirement by deploying a crafted web site and conducting a DNS spoofing attack against a mozilla.org subdomain.

A mechanism was discovered that removes some bounds checking for string, array, or typed array accesses if Spectre mitigations have been disabled. This vulnerability could allow an attacker to create an arbitrary value in compiled JavaScript, for which the range analysis will infer a fully controlled, incorrect range in circumstances where users have explicitly disabled Spectre mitigations. *Note: Spectre mitigations are currently enabled for all users by default settings.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.

The UITour::onPageEvent function in Mozilla Firefox before 36.0 does not ensure that an API call originates from a foreground tab, which allows remote attackers to conduct spoofing and clickjacking attacks by leveraging access to a UI Tour web site.

After a website had entered fullscreen mode, it could have used a previously opened popup to obscure the notification that indicates the browser is in fullscreen mode. Combined with spoofing the browser chrome, this could have led to confusing the user about the current origin of the page and credential theft or other attacks. This vulnerability affects Firefox < 74.

GUI overlay vulnerability in Mozilla Firefox before 2.0.0.13 and SeaMonkey before 1.1.9 allows remote attackers to spoof form elements and redirect user inputs via a borderless XUL pop-up window from a background tab.

The docshell implementation in Mozilla Firefox before 29.0, Firefox ESR 24.x before 24.5, Thunderbird before 24.5, and SeaMonkey before 2.26 allows remote attackers to trigger the loading of a URL with a spoofed baseURI property, and conduct cross-site scripting (XSS) attacks, via a crafted web site that performs history navigation.

The file-download implementation in Mozilla Firefox before 27.0 and SeaMonkey before 2.24 does not properly restrict the timing of button selections, which allows remote attackers to conduct clickjacking attacks, and trigger unintended launching of a downloaded file, via a crafted web site.

The Public Key Pinning (PKP) implementation in Mozilla Firefox before 33.0 skips pinning checks upon an unspecified issuer-verification error, which makes it easier for remote attackers to bypass an intended pinning configuration and spoof a web site via a crafted certificate that leads to presentation of the Untrusted Connection dialog to the user.

Cross-site scripting (XSS) vulnerability in Mozilla Thunderbird 17.x through 17.0.8, Thunderbird ESR 17.x through 17.0.10, and SeaMonkey before 2.20 allows user-assisted remote attackers to inject arbitrary web script or HTML via an e-mail message containing a data: URL in a (1) OBJECT or (2) EMBED element, a related issue to CVE-2013-6674.

Bugzilla 2.x through 4.0.x before 4.0.15, 4.1.x and 4.2.x before 4.2.11, 4.3.x and 4.4.x before 4.4.6, and 4.5.x before 4.5.6 does not ensure that a scalar context is used for certain CGI parameters, which allows remote attackers to conduct cross-site scripting (XSS) attacks by sending three values for a single parameter name.

The Public Key Pinning (PKP) implementation in Mozilla Firefox before 33.0 does not properly consider the connection-coalescing behavior of SPDY and HTTP/2 in the case of a shared IP address, which allows man-in-the-middle attackers to bypass an intended pinning configuration and spoof a web site by providing a valid certificate from an arbitrary recognized Certification Authority.

Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

When a malicious application installed on the user's device broadcast an Intent to Firefox for Android, arbitrary headers could have been specified, leading to attacks such as abusing ambient authority or session fixation. This was resolved by only allowing certain safe-listed headers. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 84.

Mozilla Firefox before 47.0 allows remote attackers to spoof permission notifications via a crafted web site that rapidly triggers permission requests, as demonstrated by the microphone permission or the geolocation permission.