Mozilla Firefox vulnerabilities

CVE-2025-1935 [MEDIUM] CWE-79 CVE-2025-1935: A web page could trick a user into setting that site as the default handler for a custom URL protoco A web page could trick a user into setting that site as the default handler for a custom URL protocol. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVE-2025-5266 [MEDIUM] CWE-200 CVE-2025-5266: Script elements loading cross-origin resources generated load and error events which leaked informat Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.

CVE-2024-0749 [MEDIUM] CWE-346 CVE-2024-0749: A phishing site could have repurposed an `about:` dialog to show phishing content with an incorrect A phishing site could have repurposed an `about:` dialog to show phishing content with an incorrect origin in the address bar. This vulnerability affects Firefox < 122 and Thunderbird < 115.7.

CVE-2021-29963 [MEDIUM] CWE-345 CVE-2021-29963: Address bar search suggestions in private browsing mode were re-using session data from normal mode. Address bar search suggestions in private browsing mode were re-using session data from normal mode. *This bug only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox < 89.

CVE-2026-0887 [MEDIUM] CWE-497 CVE-2026-0887: Clickjacking issue, information disclosure in the PDF Viewer component. This vulnerability was fixed Clickjacking issue, information disclosure in the PDF Viewer component. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.

CVE-2025-5263 [MEDIUM] CWE-346 CVE-2025-5263: Error handling for script execution was incorrectly isolated from web content, which could have allo Error handling for script execution was incorrectly isolated from web content, which could have allowed cross-origin leak attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 115.24, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.

CVE-2025-27424 [MEDIUM] CWE-601 CVE-2025-27424: Websites redirecting to a non-HTTP scheme URL could allow a website address to be spoofed for a mali Websites redirecting to a non-HTTP scheme URL could allow a website address to be spoofed for a malicious page. This vulnerability was fixed in Firefox for iOS 136.

CVE-2026-84127 [MEDIUM] Mozilla Foundation Security Advisory 2026-82: CVE-2026-84127 Mozilla Foundation Security Advisory 2026-82 CVE: CVE-2026-84127 Product: Firefox Impact: high Fixed in: Firefox 155

CVE-2025-23108 [MEDIUM] CWE-79 CVE-2025-23108: Opening Javascript links in a new tab via long-press in the Firefox iOS client could result in a mal Opening Javascript links in a new tab via long-press in the Firefox iOS client could result in a malicious script spoofing the URL of the new tab. This vulnerability was fixed in Firefox for iOS 134.

CVE-2025-27425 [MEDIUM] CWE-287 CVE-2025-27425: Scanning certain QR codes that included text with a website URL could allow the URL to be opened wit Scanning certain QR codes that included text with a website URL could allow the URL to be opened without presenting the user with a confirmation alert first. This vulnerability was fixed in Firefox for iOS 136.

CVE-2006-3802 [MEDIUM] CVE-2006-3802: Mozilla Firefox before 1.5.0.5, Thunderbird before 1.5.0.5, and SeaMonkey before 1.0.3 allows remote Mozilla Firefox before 1.5.0.5, Thunderbird before 1.5.0.5, and SeaMonkey before 1.0.3 allows remote attackers to hijack native DOM methods from objects in another domain and conduct cross-site scripting (XSS) attacks using DOM methods of the top-level object.

CVE-2006-1942 [MEDIUM] CVE-2006-1942: Mozilla Firefox 1.5.0.2 and possibly other versions before 1.5.0.4, Netscape 8.1, 8.0.4, and 7.2, an Mozilla Firefox 1.5.0.2 and possibly other versions before 1.5.0.4, Netscape 8.1, 8.0.4, and 7.2, and K-Meleon 0.9.13 allows user-assisted remote attackers to open local files via a web page with an IMG element containing a SRC attribute with a non-image file:// URL, then tricking the user into selecting View Image for the broken image, as demonstrated using

CVE-2008-2933 [LOW] CWE-20 CVE-2008-2933: Mozilla Firefox before 2.0.0.16, and 3.x before 3.0.1, interprets '|' (pipe) characters in a command Mozilla Firefox before 2.0.0.16, and 3.x before 3.0.1, interprets '|' (pipe) characters in a command-line URI as requests to open multiple tabs, which allows remote attackers to access chrome:i URIs, or read arbitrary local files via manipulations involving a series of URIs that is not entirely handled by a vector application, as exploited in conjunction

CVE-2009-1304 [MEDIUM] CWE-399 CVE-2009-1304: The JavaScript engine in Mozilla Firefox 3.x before 3.0.9, Thunderbird before 2.0.0.22, and SeaMonke The JavaScript engine in Mozilla Firefox 3.x before 3.0.9, Thunderbird before 2.0.0.22, and SeaMonkey before 1.1.16 allows remote attackers to cause a denial of service (application crash) and possibly trigger memory corruption via vectors involving (1) js_FindPropertyHelper, related to the definitions of Math and Date; and (2) js_CheckRedeclaration.

CVE-2010-1990 [MEDIUM] CWE-399 CVE-2010-1990: Mozilla Firefox 3.6.x, 3.5.x, 3.0.19, and earlier, and SeaMonkey, executes a mail application in sit Mozilla Firefox 3.6.x, 3.5.x, 3.0.19, and earlier, and SeaMonkey, executes a mail application in situations where an IFRAME element has a mailto: URL in its SRC attribute, which allows remote attackers to cause a denial of service (excessive application launches) via an HTML document with many IFRAME elements.

CVE-2009-1303 [MEDIUM] CWE-16 CVE-2009-1303: The browser engine in Mozilla Firefox before 3.0.9, Thunderbird before 2.0.0.22, and SeaMonkey befor The browser engine in Mozilla Firefox before 3.0.9, Thunderbird before 2.0.0.22, and SeaMonkey before 1.1.16 allows remote attackers to cause a denial of service (application crash) and possibly trigger memory corruption via vectors related to nsSVGElement::BindToTree.

CVE-2005-0588 [MEDIUM] CVE-2005-0588: Firefox before 1.0.1 and Mozilla before 1.7.6 does not restrict xsl:include and xsl:import tags in X Firefox before 1.0.1 and Mozilla before 1.7.6 does not restrict xsl:include and xsl:import tags in XSLT stylesheets to the current domain, which allows remote attackers to determine the existence of files on the local system.

CVE-2010-1986 [MEDIUM] CVE-2010-1986: Mozilla Firefox 3.6.3 on Windows XP SP3 allows remote attackers to cause a denial of service (memory Mozilla Firefox 3.6.3 on Windows XP SP3 allows remote attackers to cause a denial of service (memory consumption and application crash) via JavaScript code that creates multiple arrays containing elements with long string values, and then appends long strings to the content of a P element, related to the gfxWindowsFontGroup::MakeTextRun function in xul.dll, a

CVE-2005-1575 [MEDIUM] CVE-2005-1575: The file download dialog in Mozilla Firefox 0.10.1 and 1.0 for Windows allows remote attackers to hi The file download dialog in Mozilla Firefox 0.10.1 and 1.0 for Windows allows remote attackers to hide the real file types of downloaded files via the Content-Type HTTP header and a filename containing whitespace, dots, or ASCII byte 160.

CVE-2005-1158 [MEDIUM] CVE-2005-1158: Multiple "missing security checks" in Firefox before 1.0.3 allow remote attackers to inject arbitrar Multiple "missing security checks" in Firefox before 1.0.3 allow remote attackers to inject arbitrary Javascript into privileged pages using the _search target of the Firefox sidebar.