An attacker could have written a value to the first element in a zero-length JavaScript array. Although the array was zero-length, the value was not written to an invalid memory address. This vulnerability affects Firefox < 104.

When a ServiceWorker intercepted a request with <code>FetchEvent</code>, the origin of the request was lost after the ServiceWorker took ownership of it. This had the effect of negating SameSite cookie protections. This was addressed in the spec and then in browsers. This vulnerability affects Firefox ESR < 102.5, Thunderbird < 102.5, and Firefox < 107.

When downloading an update for an addon, the downloaded addon update's version was not verified to match the version selected from the manifest. If the manifest had been tampered with on the server, an attacker could trick the browser into downgrading the addon to a prior version. This vulnerability affects Firefox < 102.

A malicious website that could create a popup could have resized the popup to overlay the address bar with its own content, resulting in potential user confusion or spoofing attacks. <br>*This bug only affects Thunderbird for Linux. Other operating systems are unaffected.*. This vulnerability affects Firefox < 102, Firefox ESR < 91.11, Thunderbird < 102, and Thunderbird < 91.11.

The <code>ms-msdt</code>, <code>search</code>, and <code>search-ms</code> protocols deliver content to Microsoft applications, bypassing the browser, when a user accepts a prompt. These applications have had known vulnerabilities, exploited in the wild (although we know of none exploited through Thunderbird), so in this release Thunderbird has blocked these protocols from prompting the user to open them.<br>*This bug only affects Thunderbird on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 102, Firefox ESR < 91.11, Thunderbird < 102, and Thunderbird < 91.11.

When exiting fullscreen mode, an iframe could have confused the browser about the current state of fullscreen, resulting in potential user confusion or spoofing attacks. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

When reusing existing popups Firefox would have allowed them to cover the fullscreen notification UI, which could have enabled browser spoofing attacks. This vulnerability affects Thunderbird < 91.9, Firefox ESR < 91.9, and Firefox < 100.

The parent process would not properly check whether the Speech Synthesis feature is enabled, when receiving instructions from a child process. This vulnerability affects Thunderbird < 91.9.

WebExtensions with the correct permissions were able to create and install ServiceWorkers for third-party websites that would not have been uninstalled with the extension. This vulnerability affects Firefox < 95.

When invoking protocol handlers for external protocols, a supplied parameter URL containing spaces was not properly escaped. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

When receiving an OpenPGP/MIME signed email message that contains an additional outer MIME message layer, for example a message footer added by a mailing list gateway, Thunderbird only considered the inner signed message for the signature validity. This gave the false impression that the additional contents were also covered by the digital signature. Starting with Thunderbird version 91.4.1, only the signature that belongs to the top level MIME part will be considered for the displayed status. This vulnerability affects Thunderbird < 91.4.1.

When delegating navigations to the operating system, Firefox would accept the `mk` scheme which might allow attackers to launch pages and execute scripts in Internet Explorer in unprivileged mode. *This bug only affects Firefox for Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 92, Thunderbird < 91.1, Thunderbird < 78.14, Firefox ESR < 78.14, and Firefox ESR < 91.1.

Through use of reportValidity() and window.open(), a plain-text validation message could have been overlaid on another origin, leading to possible user confusion and spoofing attacks. This vulnerability affects Firefox < 93, Thunderbird < 91.2, and Firefox ESR < 91.2.

After a HelloRetryRequest has been sent, the client may negotiate a lower protocol that TLS 1.3, resulting in an invalid state transition in the TLS State Machine. If the client gets into this state, incoming Application Data records will be ignored. This vulnerability affects Firefox < 72.

A same-origin policy violation occurs allowing the theft of cross-origin images through a combination of SVG filters and a &lt;canvas&gt; element due to an error in how same-origin policy is applied to cached image content. The resulting same-origin policy violation could allow for data theft. This vulnerability affects Firefox < 69, Thunderbird < 68.1, Thunderbird < 60.9, Firefox ESR < 60.9, and Firefox ESR < 68.1.

When a user downloaded a file in Firefox for Android, if a cookie is set, it would have been re-sent during a subsequent file download operation on the same domain, regardless of whether the original and subsequent request were in private and non-private browsing modes. *Note: This issue only affected Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 83.

OCSP revocation status of recipient certificates was not checked when sending S/Mime encrypted email, and revoked certificates would be accepted. Thunderbird versions from 68 to 102.9.1 were affected by this bug. This vulnerability affects Thunderbird < 102.10.

Malicious websites could have tricked users into accepting launching a program to handle an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

Malicious websites could have confused Firefox into showing the wrong origin when asking to launch a program and handling an external URL protocol. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

The HTTP/2 protocol does not consider the role of the TCP congestion window in providing information about content length, which makes it easier for remote attackers to obtain cleartext data by leveraging a web-browser configuration in which third-party cookies are sent, aka a "HEIST" attack.

The HTTPS protocol does not consider the role of the TCP congestion window in providing information about content length, which makes it easier for remote attackers to obtain cleartext data by leveraging a web-browser configuration in which third-party cookies are sent, aka a "HEIST" attack.

Bugzilla 2.20.x before 2.20.5, 2.22.x before 2.22.3, and 3.0.x before 3.0.3 on Windows does not delete the temporary files associated with uploaded attachments, which allows local users to obtain sensitive information by reading these files, a different vulnerability than CVE-2011-2977.

mailnews in Mozilla Thunderbird before 2.0.0.18 and SeaMonkey before 1.1.13, when JavaScript is enabled in mail, allows remote attackers to obtain sensitive information about the recipient, or comments in forwarded mail, via script that reads the (1) .documentURI or (2) .textContent DOM properties.

Mozilla Firefox before 49.0 allows user-assisted remote attackers to obtain sensitive full-pathname information during a local-file drag-and-drop operation via crafted JavaScript code.

Web content could access information in the HTTP cache if e10s is disabled. This can reveal some visited URLs and the contents of those pages. This issue affects Firefox 48 and 49. This vulnerability affects Firefox < 49.0.2.

Mozilla Firefox before 48.0 and Firefox ESR 45.x before 45.3 allow user-assisted remote attackers to bypass the Same Origin Policy, and conduct Universal XSS (UXSS) attacks or read arbitrary files, by arranging for the presence of a crafted HTML document and a crafted shortcut file in the same local directory.

Mozilla Firefox before 48.0, Firefox ESR < 45.4 and Thunderbird < 45.4 allow remote attackers to obtain sensitive information about the previously retrieved page via Resource Timing API calls.

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 allow remote attackers to bypass the same origin policy and access portions of data from another domain via a JavaScript URL that redirects to the target resource, which generates an error if the target data does not have JavaScript syntax, which can be accessed using the window.onerror DOM API.

Mozilla Firefox before 49.0 does not properly restrict the scheme in favicon requests, which might allow remote attackers to obtain sensitive information via unspecified vectors, as demonstrated by a jar: URL for a favicon resource.

Mozilla Firefox 2.x before 2.0.0.18, Thunderbird 2.x before 2.0.0.18, and SeaMonkey 1.x before 1.1.13 do not properly change the source URI when processing a canvas element and an HTTP redirect, which allows remote attackers to bypass the same origin policy and access arbitrary images that are not directly accessible to the attacker. NOTE: this issue can be leveraged to enumerate software on the client by performing redirections related to moz-icon.

Under certain circumstances, asynchronous functions could have caused a navigation to fail but expose the target URL. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

Adobe Flash Player 9.0.124.0 and earlier, when a Mozilla browser is used, does not properly interpret jar: URLs, which allows attackers to obtain sensitive information via unknown vectors.

The XBM decoder in Mozilla Firefox before 2.0.0.17 and SeaMonkey before 1.1.12 allows remote attackers to read uninitialized memory, and possibly obtain sensitive information in opportunistic circumstances, via a crafted XBM image file.

Mozilla Firefox before 2.0.0.15 and SeaMonkey before 1.1.10 do not properly handle an invalid .properties file for an add-on, which allows remote attackers to read uninitialized memory, as demonstrated by use of ISO 8859 encoding instead of UTF-8 encoding in a French .properties file.

Mozilla Firefox 2.0.0.11, 3.0b2, and possibly earlier versions, when prompting for HTTP Basic Authentication, displays the site requesting the authentication after the Realm text, which might make it easier for remote HTTP servers to conduct phishing and spoofing attacks.

modules/libpr0n/decoders/bmp/nsBMPDecoder.cpp in Mozilla Firefox before 2.0.0.12, Thunderbird before 2.0.0.12, and SeaMonkey before 1.1.8 does not properly perform certain calculations related to the mColors table, which allows remote attackers to read portions of memory uninitialized via a crafted 8-bit bitmap (BMP) file that triggers an out-of-bounds read within the heap, as demonstrated using a CANVAS element; or cause a denial of service (application crash) via a crafted 8-bit bitmap file that triggers an out-of-bounds read. NOTE: the initial public reports stated that this affected Firefox in Ubuntu 6.06 through 7.10.

Gecko-based browsers, including Mozilla Firefox before 2.0.0.12 and SeaMonkey before 1.1.8, modify the .href property of stylesheet DOM nodes to the final URI of a 302 redirect, which might allow remote attackers to bypass the Same Origin Policy and read sensitive information from the original URL, such as with Single-Signon systems.

If a text string that happens to be a filename in the operating system's native format is dragged and dropped onto the addressbar the specified local file will be opened. This is contrary to policy and is what would happen if the string were the equivalent "file:" URL. This vulnerability affects Firefox < 60.

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.

The Find API for WebExtensions can search some privileged pages, such as "about:debugging", if these pages are open in a tab. This could allow a malicious WebExtension to search for otherwise protected data if a user has it open. This vulnerability affects Firefox < 59.

Under certain circumstances the "fetch()" API can return transient local copies of resources that were sent with a "no-store" or "no-cache" cache header instead of downloading a copy from the network as it should. This can result in previously stored, locally cached data of a website being accessible to users if they share a common profile while browsing. This vulnerability affects Firefox ESR < 52.7 and Firefox < 59.

A legacy extension's non-contentaccessible, defined resources can be loaded by an arbitrary web page through script. This script does this by using a maliciously crafted path string to reference the resources. Note: this vulnerability does not affect WebExtensions. This vulnerability affects Firefox < 59.

Mozilla Firefox 2.0 before 2.0.0.8 allows remote attackers to obtain sensitive system information by using the addMicrosummaryGenerator sidebar method to access file: URIs.

WebExtensions may use "view-source:" URLs to view local "file:" URL content, as well as content stored in "about:cache", bypassing restrictions that only allow WebExtensions to view specific content. This vulnerability affects Firefox < 59.

Same-origin protections for the PDF viewer can be bypassed, allowing a malicious site to intercept messages meant for the viewer. This could allow the site to retrieve PDF files restricted to viewing by an authenticated user on a third-party website. This vulnerability affects Firefox ESR < 52.8 and Firefox < 60.

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.

Image for moz-icons can be accessed through the "moz-icon:" protocol through script in web content even when otherwise prohibited. This could allow for information leakage of which applications are associated with specific MIME types by a malicious page. This vulnerability affects Firefox < 59.

If a URL using the "file:" protocol is dragged and dropped onto an open tab that is running in a different child process the tab will open a local file corresponding to the dropped URL, contrary to policy. One way to make the target tab open more reliably in a separate process is to open it with the "noopener" keyword. This vulnerability affects Firefox < 60.

If the "app.support.baseURL" preference is changed by a malicious local program to contain HTML and script content, this content is not sanitized. It will be executed if a user loads "chrome://browser/content/preferences/in-content/preferences.xul" directly in a tab and executes a search. This stored preference is also executed whenever an EME video player plugin displays a CDM-disabled message as a notification message. This vulnerability affects Firefox < 59.

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.