Sites can bypass security checks on permissions to install lightweight themes by manipulating the "baseURI" property of the theme element. This could allow a malicious site to install a theme without user interaction which could contain offensive or embarrassing images. This vulnerability affects Thunderbird < 52.8, Thunderbird ESR < 52.8, Firefox < 60, and Firefox ESR < 52.8.

If a site is loaded over a HTTPS connection but loads a favicon resource over HTTP, the mixed content warning is not displayed to users. This vulnerability affects Firefox < 63.

Mozilla Firefox before 1.0 truncates long filenames in the file download dialog box, which makes it easier for remote attackers to trick users into downloading files with dangerous extensions.

Mozilla Firefox before 29.0 on Android allows remote attackers to spoof the address bar via crafted JavaScript code that uses DOM events to prevent the reemergence of the actual address bar after scrolling has taken it off of the screen.

The confirm_create_account function in the account-creation feature in token.cgi in 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 specify a scalar context for the realname parameter, which allows remote attackers to create accounts with unverified e-mail addresses by sending three realname values with realname=login_name as the second, as demonstrated by selecting an e-mail address with a domain name for which group privileges are automatically granted.

The Internationalized Domain Name (IDN) display algorithm in Mozilla Firefox before 22.0 does not properly handle the .com, .name, and .net top-level domains, which allows remote attackers to spoof the address bar via unspecified homograph characters.

Auth/Verify/LDAP.pm in Bugzilla 2.x and 3.x before 3.6.11, 3.7.x and 4.0.x before 4.0.8, 4.1.x and 4.2.x before 4.2.3, and 4.3.x before 4.3.3 does not restrict the characters in a username, which might allow remote attackers to inject data into an LDAP directory via a crafted login attempt.

Mozilla Firefox 4.x through 9.0, Thunderbird 5.0 through 9.0, and SeaMonkey before 2.7 allow remote attackers to bypass the HTML5 frame-navigation policy and replace arbitrary sub-frames by creating a form submission target with a sub-frame's name attribute.

Mozilla Firefox before 3.6.18, Thunderbird before 3.1.11, and SeaMonkey through 2.0.14 do not distinguish between cookies for two domain names that differ only in a trailing dot, which allows remote web servers to bypass the Same Origin Policy via Set-Cookie headers.

Visual truncation vulnerability in Mozilla Firefox before 3.0.14, and 3.5.x before 3.5.3, allows remote attackers to trigger a vertical scroll and spoof URLs via unspecified Unicode characters with a tall line-height property.

Punycode format text will be displayed for entire qualified international domain names in some instances when a sub-domain triggers the punycode display instead of the primary domain being displayed in native script and the sub-domain only displaying as punycode. This could be used for limited spoofing attacks due to user confusion. This vulnerability affects Firefox < 57.

If a server sends two Strict-Transport-Security (STS) headers for a single connection, they will be rejected as invalid and HTTP Strict Transport Security (HSTS) will not be enabled for the connection. This vulnerability affects Firefox < 55.

When a page's content security policy (CSP) header contains a "sandbox" directive, other directives are ignored. This results in the incorrect enforcement of CSP. This vulnerability affects Thunderbird < 52.3, Firefox ESR < 52.3, and Firefox < 55.

The "export" function in the Certificate Viewer can force local filesystem navigation when the "common name" in a certificate contains slashes, allowing certificate content to be saved in unsafe locations with an arbitrary filename. This vulnerability affects Firefox < 51.

The internal feed reader APIs that crossed the sandbox barrier allowed for a sandbox escape and escalation of privilege if combined with another vulnerability that resulted in remote code execution inside the sandboxed process. This vulnerability affects Firefox ESR < 52.1 and Firefox < 53.

The CSS parser in 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 ignores the '\0' escaped null character, which might allow remote attackers to bypass protection mechanisms such as sanitization routines.