An audio capture session can started under an incorrect origin from the site making the capture request. Users are still prompted to allow the request but the prompt can display the wrong origin, leading to user confusion about which site is making the request to capture an audio stream. This vulnerability affects Firefox < 58.

A compromised content process could have allowed for the arbitrary loading of cross-origin pages. This vulnerability affects Firefox < 131, Firefox ESR < 128.3, Firefox ESR < 115.16, Thunderbird < 128.3, and Thunderbird < 131.

Same-origin policy bypass in the Networking: JAR component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

A same-origin policy violation could have allowed the theft of cross-origin URL entries, leaking the result of a redirect, via `performance.getEntries()`. This vulnerability affects Firefox < 106, Firefox ESR < 102.4, and Thunderbird < 102.4.

A same-origin policy violation allowing the theft of cross-origin URL entries when using a meta http-equiv="refresh" on a page to cause a redirection to another site using performance.getEntries(). This is a same-origin policy violation and could allow for data theft. This vulnerability affects Firefox < 62, Firefox ESR < 60.2, and Thunderbird < 60.2.1.

A same-origin policy violation allowing the theft of cross-origin URL entries when using the Javascript location property to cause a redirection to another site using performance.getEntries(). This is a same-origin policy violation and could allow for data theft. This vulnerability affects Thunderbird < 60.4, Firefox ESR < 60.4, and Firefox < 64.

Same-origin policy bypass in the DOM: Navigation component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Site isolation issue in the Networking: HTTP component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Site isolation issue in the Networking component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

Same-origin policy bypass in the Networking: DNS component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Same-origin policy bypass in the Networking: Cookies component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

When a link to an external protocol was clicked, a prompt was presented that allowed the user to choose what application to open it in. An attacker could induce that prompt to be associated with an origin they didn't control, resulting in a spoofing attack. This was fixed by changing external protocol prompts to be tab-modal while also ensuring they could not be incorrectly associated with a different origin. This vulnerability affects Firefox < 82.

Same-origin policy bypass in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 142, Firefox ESR 115.27, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.

Offscreen Canvas did not properly track cross-origin tainting, which could have been used to access image data from another site in violation of same-origin policy. This vulnerability affects Firefox < 116, Firefox ESR < 102.14, and Firefox ESR < 115.1.

A website could prevent a user from exiting full-screen mode via alert and prompt calls. This could lead to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 115.

Long hostnames in URLs could be leveraged to obscure the actual host of the website or spoof the website address. This vulnerability was fixed in Firefox for iOS 134.

Images from a different domain can be read using a canvas object in some circumstances. This could be used to steal image data from a different site in violation of same-origin policy. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

The internal WebBrowserPersist code does not use correct origin context for a resource being saved. This manifests when sub-resources are loaded as part of "Save Page As..." functionality. For example, a malicious page could recover a visitor's Windows username and NTLM hash by including resources otherwise unreachable to the malicious page, if they can convince the visitor to save the complete web page. Similarly, SameSite cookies are sent on cross-origin requests when the "Save Page As..." menu item is selected to save a page, which can result in saving the wrong version of resources based on those cookies. This vulnerability affects Firefox < 63.

Navigations were being allowed when dragging a URL from a cross-origin iframe into the same tab which could lead to website spoofing attacks This vulnerability affects Firefox < 109, Firefox ESR < 102.7, and Thunderbird < 102.7.

Dragging a URL from a cross-origin iframe that was removed during the drag could have led to user confusion and website spoofing attacks. This vulnerability affects Firefox < 111, Firefox ESR < 102.9, and Thunderbird < 102.9.

Mozilla Firefox before 16.0.1, Firefox ESR 10.x before 10.0.9, Thunderbird before 16.0.1, Thunderbird ESR 10.x before 10.0.9, and SeaMonkey before 2.13.1 omit a security check in the defaultValue function during the unwrapping of security wrappers, which allows remote attackers to bypass the Same Origin Policy and read the properties of a Location object, or execute arbitrary JavaScript code, via a crafted web site.

Remote Agent, used in WebDriver, did not validate the Host or Origin headers. This could have allowed websites to connect back locally to the user's browser to control it. <br>*This bug only affected Firefox when WebDriver was enabled, which is not the default configuration.*. This vulnerability affects Firefox < 97.

Response header name interning does not have same-origin protections and these headers are stored in a global registry. This allows stored header names to be available cross-origin. This vulnerability affects Firefox < 55.

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.

Same-origin policy bypass in the Request Handling component. This vulnerability was fixed in Firefox 146, Firefox ESR 115.31, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.

The Upgrade-Insecure-Requests (UIR) specification states that if UIR is enabled through Content Security Policy (CSP), navigation to a same-origin URL must be upgraded to HTTPS. Firefox will incorrectly navigate to an HTTP URL rather than perform the security upgrade requested by the CSP in some circumstances, allowing for potential man-in-the-middle attacks on the linked resources. This vulnerability affects Firefox < 66.

Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 148.0.2.

The Opportunistic Encryption feature of HTTP2 (RFC 8164) allows a connection to be transparently upgraded to TLS while retaining the visual properties of an HTTP connection, including being same-origin with unencrypted connections on port 80. However, if a second encrypted port on the same IP address (e.g. port 8443) did not opt-in to opportunistic encryption; a network attacker could forward a connection from the browser to port 443 to port 8443, causing the browser to treat the content of port 8443 as same-origin with HTTP. This was resolved by disabling the Opportunistic Encryption feature, which had low usage. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

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.

Site isolation issue in the Graphics: WebRender component. This vulnerability was fixed in Firefox 153, Firefox ESR 115.38, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.

Site isolation issue in the Graphics component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.

By observing the stack trace for JavaScript errors in web workers, it was possible to leak the result of a cross-origin redirect. This applied only to content that can be parsed as script. This vulnerability affects Firefox < 79, Firefox ESR < 68.11, Firefox ESR < 78.1, Thunderbird < 68.11, and Thunderbird < 78.1.

When viewing an email message A, which contains an attached message B, where B is encrypted or digitally signed or both, Thunderbird may show an incorrect encryption or signature status. After opening and viewing the attached message B, when returning to the display of message A, the message A might be shown with the security status of message B. This vulnerability affects Thunderbird < 91.9.

The Pocket toolbar button, once activated, listens for events fired from it's own pages but does not verify the origin of incoming events. This allows content from other origins to fire events and inject content and commands into the Pocket context. Note: this issue does not affect users with e10s enabled. This vulnerability affects Firefox ESR < 45.6 and Firefox < 50.1.

The (1) WebGL.compressedTexImage2D and (2) WebGL.compressedTexSubImage2D functions in Mozilla Firefox before 28.0 and SeaMonkey before 2.25 allow remote attackers to bypass the Same Origin Policy and render content in a different domain via unspecified vectors.

The Web workers implementation in Mozilla Firefox before 27.0, Firefox ESR 24.x before 24.3, Thunderbird before 24.3, and SeaMonkey before 2.24 allows remote attackers to bypass the Same Origin Policy and obtain sensitive authentication information via vectors involving error messages.

By encoding Unicode whitespace characters within the From email header, an attacker can spoof the sender email address that Thunderbird displays. This vulnerability affects Thunderbird < 68.8.0.

The PDF reader in Mozilla Firefox before 39.0.3, Firefox ESR 38.x before 38.1.1, and Firefox OS before 2.2 allows remote attackers to bypass the Same Origin Policy, and read arbitrary files or gain privileges, via vectors involving crafted JavaScript code and a native setter, as exploited in the wild in August 2015.

Inappropriate implementation in Media in Google Chrome prior to 148.0.7778.96 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Medium)

Insufficient policy enforcement in Autofill in Google Chrome prior to 148.0.7778.96 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Medium)

Inappropriate implementation in Navigation in Google Chrome prior to 147.0.7727.55 allowed a remote attacker who had compromised the renderer process to leak cross-origin data via a crafted HTML page. (Chromium security severity: Low)

The Vue.js Devtools extension was found to leak screenshot data back to a malicious web page via the standard `postMessage()` API. By creating a malicious web page with an iFrame targeting a sensitive resource (i.e. a locally accessible file or sensitive website), and registering a listener on the web page, the extension sent messages back to the listener, containing the base64 encoded screenshot data of the sensitive resource.

Inappropriate implementation in performance APIs in Google Chrome prior to 89.0.4389.72 allowed a remote attacker to leak cross-origin data via a crafted HTML page.

A logic issue was addressed with improved state management. This issue is fixed in Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, visionOS 26.4. A malicious website may be able to access script message handlers intended for other origins.

Insufficient policy enforcement in Data Transfer in Google Chrome prior to 128.0.6613.84 allowed a remote attacker who convinced a user to engage in specific UI gestures to leak cross-origin data via a crafted HTML page. (Chromium security severity: Medium)

MSA FieldServer Gateway 5.0.0 through 6.5.2 allows cross-origin WebSocket hijacking.

Inappropriate implementation in DeviceBoundSessionCredentials in Google Chrome prior to 149.0.7827.197 allowed a remote attacker to bypass same origin policy via a crafted HTML page. (Chromium security severity: High)

Insufficient policy enforcement in WebView in Google Chrome on Android prior to 149.0.7827.53 allowed a remote attacker to leak cross-origin data via a crafted HTML page. (Chromium security severity: Medium)