CVE-2025-0243

Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6

Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128.5, and Thunderbird 128.5. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.

CVSS 3.1 · 5.1 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-0247

Memory safety bugs fixed in Firefox 134 and Thunderbird 134

Memory safety bugs present in Firefox 133 and Thunderbird 133. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 134 and Thunderbird 134.

CVSS 3.1 · 9.8 Critical EPSS 10.7% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-1009

Use-after-free in XSLT

An attacker could have caused a use-after-free via crafted XSLT data, leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

CVSS 3.1 · 9.8 Critical EPSS 1.2% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1011

A bug in WebAssembly code generation could result in a crash

A bug in WebAssembly code generation could have lead to a crash. It may have been possible for an attacker to leverage this to achieve code execution. This vulnerability was fixed in Firefox 135, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1019

Fullscreen notification not properly displayed

The z-order of the browser windows could be manipulated to hide the fullscreen notification. This could potentially be leveraged to perform a spoofing attack. This vulnerability was fixed in Firefox 135 and Thunderbird 135.

CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-1013

Potential opening of private browsing tabs in normal browsing windows

A race condition could have led to private browsing tabs being opened in normal browsing windows. This could have resulted in a potential privacy leak. This vulnerability was fixed in Firefox 135, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1014

Certificate length was not properly checked

Certificate length was not properly checked when added to a certificate store. In practice only trusted data was processed. This vulnerability was fixed in Firefox 135, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

CVSS 3.1 · 8.8 High EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1016

Memory safety bugs fixed in Firefox 135, Thunderbird 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 115.20, and Thunderbird 128.7

Memory safety bugs present in Firefox 134, Thunderbird 134, Firefox ESR 115.19, Firefox ESR 128.6, Thunderbird 115.19, and Thunderbird 128.6. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.

CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1015

Unsanitized address book fields

The Thunderbird Address Book URI fields contained unsanitized links. This could be used by an attacker to create and export an address book containing a malicious payload in a field. For example, in the “Other” field of the Instant Messaging section. If another user imported the address book, clicking on the link could result in opening a web page inside Thunderbird, and that page could execute (unprivileged) JavaScript. This vulnerability was fixed in Thunderbird 128.7 and Thunderbird 135.

CVSS 3.1 · 5.4 Medium EPSS 1.4% KEV · Not listed

Vendors

Mozilla Redhat

Products

Thunderbird Enterprise Linux Rhel Aus and 3 more

CVE-2025-1414

Memory safety bugs fixed in Firefox 135.0.1

Memory safety bugs present in Firefox 135. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 135.0.1.

CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox

CVE-2025-1939

Tapjacking in Android Custom Tabs using transition animations

Android apps can load web pages using the Custom Tabs feature. This feature supports a transition animation that could have been used to trick a user into granting sensitive permissions by hiding what the user was actually clicking. This vulnerability was fixed in Firefox 136.

CVSS 3.1 · 3.9 Low EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox

CVE-2025-1940

Android Intent confirmation prompt tapjacking using Select options

A select option could partially obscure the confirmation prompt shown before launching external apps. This could be used to trick a user in to launching an external app unexpectedly. *This issue only affects Android versions of Firefox.*. This vulnerability was fixed in Firefox 136.

CVSS 3.1 · 7.1 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox

CVE-2025-1941

Lock screen setting bypass in Firefox Focus for Android

Under certain circumstances, a user opt-in setting that Focus should require authentication before use could have been be bypassed (distinct from CVE-2025-0245). This vulnerability was fixed in Firefox 136.

CVSS 3.1 · 9.1 Critical EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox

CVE-2025-1942

Disclosure of uninitialized memory when .toUpperCase() causes string to get longer

When String.toUpperCase() caused a string to get longer it was possible for uninitialized memory to be incorporated into the result string. This vulnerability was fixed in Firefox 136 and Thunderbird 136.

CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-1936

Adding %00 and a fake extension to a jar: URL changed the interpretation of the contents

jar: URLs retrieve local file content packaged in a ZIP archive. The null and everything after it was ignored when retrieving the content from the archive, but the fake extension after the null was used to determine the type of content. This could have been used to hide code in a web extension disguised as something else like an image. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVSS 3.1 · 7.3 High EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1938

Memory safety bugs fixed in Firefox 136, Thunderbird 136, Firefox ESR 128.8, and Thunderbird 128.8

Memory safety bugs present in Firefox 135, Thunderbird 135, Firefox ESR 128.7, and Thunderbird 128.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVSS 3.1 · 6.5 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1943

Memory safety bugs fixed in Firefox 136 and Thunderbird 136

Memory safety bugs present in Firefox 135 and Thunderbird 135. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 136 and Thunderbird 136.

CVSS 3.1 · 8.2 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-27426

Firefox Mobile iOS Full Address Bar Spoof Using Server-Side Redirect to internal error page

Malicious websites utilizing a server-side redirect to an internal error page could result in a spoofed website URL. This vulnerability was fixed in Firefox for iOS 136.

CVSS 3.1 · 5.4 Medium EPSS < 1% KEV · Not listed

Vendors

Apple Mozilla

Products

Iphone Os Firefox

CVE-2025-27424

Firefox Mobile iOS Address Bar Spoof Using Server-Side Redirect to non-http Scheme

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.

CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed

Vendors

Apple Mozilla

Products

Iphone Os Firefox

CVE-2025-26695

Downloading of OpenPGP keys from WKD used incorrect padding

When requesting an OpenPGP key from a WKD server, an incorrect padding size was used and a network observer could have learned the length of the requested email address. This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8.

CVSS 3.1 · 5.3 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Thunderbird