A clipboard "paste" button could persist across tabs which allowed a spoofing attack. This vulnerability affects Firefox < 132, Firefox ESR < 128.4, Thunderbird < 128.4, and Thunderbird < 132.

Truncation of a long URL could have allowed origin spoofing in a permission prompt. This vulnerability affects Firefox < 132, Firefox ESR < 128.4, Thunderbird < 128.4, and Thunderbird < 132.

Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context. This allowed the execution of scripts that should have been blocked, albeit with a unique opaque origin. This vulnerability affects Firefox < 76.

When checking if the Browsing Context had been discarded in `HttpBaseChannel`, if the load group was not available then it was assumed to have already been discarded which was not always the case for private channels after the private session had ended. This vulnerability affects Firefox < 117, Firefox ESR < 115.2, and Thunderbird < 115.2.

If an insecure element was added to a page after a delay, Firefox would not replace the secure icon with a mixed content security status This vulnerability affects Firefox for iOS < 124.

Incorrect code generation could have led to unexpected numeric conversions and potential undefined behavior.*Note:* This issue only affects 32-bit ARM devices. This vulnerability affects Firefox < 123, Firefox ESR < 115.8, and Thunderbird < 115.8.

A malicious Android application could craft an Intent that would have been processed by Firefox for Android and potentially result in a file overwrite in the user's profile directory. One exploitation vector for this would be to supply a user.js file providing arbitrary malicious preference values. Control of arbitrary preferences can lead to sufficient compromise such that it is generally equivalent to arbitrary code execution.<br> *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.7.

When the number of cookies per domain was exceeded in `document.cookie`, the actual cookie jar sent to the host was no longer consistent with expected cookie jar state. This could have caused requests to be sent with some cookies missing. This vulnerability affects Firefox < 116, Firefox ESR < 102.14, and Firefox ESR < 115.1.

In a non-standard configuration of Firefox, an integer overflow could have occurred based on network traffic (possibly under influence of a local unprivileged webpage), leading to an out-of-bounds write to privileged process memory. *This bug only affects Firefox if a non-standard preference allowing non-HTTPS Alternate Services (`network.http.altsvc.oe`) is enabled.* This vulnerability affects Firefox < 118.

A website could have obscured the full screen notification by using the file open dialog. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 116, Firefox ESR < 115.2, and Thunderbird < 115.2.

An attacker could write data to the user's clipboard, bypassing the user prompt, during a certain sequence of navigational events. This vulnerability affects Firefox < 129, Firefox ESR < 128.3, and Thunderbird < 128.3.

When combining CSS properties for overflow and transform, the mouse cursor could interact with different coordinates than displayed. This vulnerability affects Firefox ESR < 102.1, Firefox ESR < 91.12, Firefox < 103, Thunderbird < 102.1, and Thunderbird < 91.12.

A crafted S/MIME message consisting of an inner encryption layer and an outer SignedData layer was shown as having a valid digital signature, although the signer might have had no access to the contents of the encrypted message, and might have stripped a different signature from the encrypted message. Previous versions had only suppressed showing a digital signature for messages with an outer multipart/signed layer. This vulnerability affects Thunderbird < 68.1.1.

When resizing a popup while requesting fullscreen access, the popup would have become unable to leave fullscreen mode. This vulnerability affects Firefox ESR < 91.5, Firefox < 96, and Thunderbird < 91.5.

Mozilla Firefox before 27.0, Firefox ESR 24.x before 24.3, Thunderbird before 24.3, and SeaMonkey before 2.24 allow remote attackers to bypass intended restrictions on window objects by leveraging inconsistency in native getter methods across different JavaScript engines.

The System Only Wrapper (SOW) implementation in Mozilla Firefox before 27.0, Firefox ESR 24.x before 24.3, Thunderbird before 24.3, and SeaMonkey before 2.24 does not prevent certain cloning operations, which allows remote attackers to bypass intended restrictions on XUL content via vectors involving XBL content scopes.

Firefox normally asks for confirmation before asking the operating system to find an application to handle a scheme that the browser does not support. It did not ask before doing so for the Usenet-related schemes news: and snews:. Since most operating systems don't have a trusted newsreader installed by default, an unscrupulous program that the user downloaded could register itself as a handler. The website that served the application download could then launch that application at will. This vulnerability affects Firefox < 130, Firefox ESR < 128.2, and Firefox ESR < 115.15.

Thunderbird allowed the Text Direction Override Unicode Character in filenames. An email attachment could be incorrectly shown as being a document file, while in fact it was an executable file. Newer versions of Thunderbird will strip the character and show the correct file extension. This vulnerability affects Thunderbird < 115.0.1 and Thunderbird < 102.13.1.

Through a series of API calls and redirects, an attacker-controlled alert dialog could have been displayed on another website (with the victim website's URL shown). This vulnerability affects Firefox < 123, Firefox ESR < 115.8, and Thunderbird < 115.8.

An attacker could cause a select dropdown to be shown over another tab; this could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 133, Firefox ESR < 128.5, Thunderbird < 133, and Thunderbird < 128.5.

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.

A missing delay in popup notifications could have made it possible for an attacker to trick a user into granting permissions. This vulnerability affects Firefox < 113, Firefox ESR < 102.11, and Thunderbird < 102.11.

When a JavaScript URL (javascript:) is evaluated and the result is a string, this string is parsed to create an HTML document, which is then presented. Previously, this document's URL (as reported by the document.location property, for example) was the originating javascript: URL which could lead to spoofing attacks; it is now correctly the URL of the originating document. This vulnerability affects Firefox < 74.

When opening a website using the `firefox://` protocol handler, SameSite cookies were not properly respected. This vulnerability affects Firefox < 123.

The incorrect domain may have been displayed in the address bar during an interrupted navigation attempt. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 133 and Thunderbird < 133.

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.

Thunderbird's handling of the X-Mozilla-External-Attachment-URL header can be exploited to execute JavaScript in the file:/// context. By crafting a nested email attachment (message/rfc822) and setting its content type to application/pdf, Thunderbird may incorrectly render it as HTML when opened, allowing the embedded JavaScript to run without requiring a file download. This behavior relies on Thunderbird auto-saving the attachment to /tmp and linking to it via the file:/// protocol, potentially enabling JavaScript execution as part of the HTML. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.

Thunderbird parses addresses in a way that can allow sender spoofing in case the server allows an invalid From address to be used. For example, if the From header contains an (invalid) value "Spoofed Name ", Thunderbird treats spoofed@example.com as the actual address. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.

A crafted URL containing specific Unicode characters could have hidden the true origin of the page, resulting in a potential spoofing attack. This vulnerability affects Firefox < 137, Firefox ESR < 128.9, Thunderbird < 137, and Thunderbird < 128.9.

Certain crafted MIME email messages that claimed to contain an encrypted OpenPGP message, which instead contained an OpenPGP signed message, were wrongly shown as being encrypted. This vulnerability affects Thunderbird < 136 and Thunderbird < 128.8.

Websites could utilize Javascript links to spoof URL addresses in the Focus navigation bar This vulnerability affects Focus for iOS < 130.

If a site had been granted the permission to open popup windows, it could cause Select elements to appear on top of another site to perform a spoofing attack. This vulnerability affects Firefox < 130, Firefox ESR < 128.2, and Thunderbird < 128.2.

A user who enables full-screen mode on a specially crafted web page could potentially be prevented from exiting full screen mode. This may allow spoofing of other sites as the address bar is no longer visible. *This bug only affects Firefox Focus for Android. Other versions of Firefox are unaffected.* This vulnerability affects Firefox < 131.

A malicious extension could have opened a popup window lacking an address bar. The title of the popup lacking an address bar should not be fully controllable, but in this situation was. This could have been used to spoof a website and attempt to trick the user into providing credentials. This vulnerability affects Firefox ESR < 78.9, Firefox < 87, and Thunderbird < 78.9.

Microsoft Edge for iOS Spoofing Vulnerability

Microsoft Edge (Chromium-based) Spoofing Vulnerability

Authentication Bypass by Spoofing vulnerability in Wpmet Wp Ultimate Review allows Functionality Bypass.This issue affects Wp Ultimate Review: from n/a through 2.3.2.

This User Activity Log WordPress plugin before 1.6.7 retrieves client IP addresses from potentially untrusted headers, allowing an attacker to manipulate its value. This may be used to hide the source of malicious traffic.

The Security & Malware scan by CleanTalk WordPress plugin before 2.121 retrieves client IP addresses from potentially untrusted headers, allowing an attacker to manipulate its value. This may be used to bypass bruteforce protection.

Authentication Bypass by Spoofing vulnerability in Metagauss RegistrationMagic allows Accessing Functionality Not Properly Constrained by ACLs.This issue affects RegistrationMagic: from n/a through 5.2.5.0.

This user-activity-log-pro WordPress plugin before 2.3.4 retrieves client IP addresses from potentially untrusted headers, allowing an attacker to manipulate its value. This may be used to hide the source of malicious traffic.

A spoofing vulnerability exists when Azure Stack fails to validate certain requests, aka 'Azure Stack Spoofing Vulnerability'.

CoreDNS through 1.10.1 enables attackers to achieve DNS cache poisoning and inject fake responses via a birthday attack.

A security vulnerability exists in Zingbox Inspector versions 1.294 and earlier, that allows for the Inspector to be susceptible to ARP spoofing.

On affected platforms running Arista EOS, maliciously formed UDP packets with source port 3503 may be accepted by EOS. UDP Port 3503 is associated with LspPing Echo Reply. This can result in unexpected behaviors, especially for UDP based services that do not perform some form of authentication.

The FluentAuth WordPress plugin before 1.0.2 prioritizes getting a visitor's IP address from certain HTTP headers over PHP's REMOTE_ADDR, which makes it possible to bypass the IP-based blocks set by the plugin.

The User Activity WordPress plugin through 1.0.1 checks headers such as the X-Forwarded-For to retrieve the IP address of the request, which could lead to IP spoofing

Microsoft Outlook for Mac Spoofing Vulnerability

The WP Limit Login Attempts WordPress plugin through 2.6.4 prioritizes getting a visitor's IP from certain HTTP headers over PHP's REMOTE_ADDR, which makes it possible to bypass IP-based restrictions on login forms.

Windows CryptoAPI Spoofing Vulnerability