CVE-2025-1935

Clickjacking the registerProtocolHandler info-bar

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.

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

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-26696

Crafted email message incorrectly shown as being encrypted

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 was fixed in Thunderbird 136 and Thunderbird 128.8.

CVSS 3.1 · 7 High EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Thunderbird

CVE-2025-3031

JIT optimization bug with different stack slot sizes

An attacker could read 32 bits of values spilled onto the stack in a JIT compiled function. This vulnerability was fixed in Firefox 137 and Thunderbird 137.

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

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-4084

Potential local code execution in "copy as cURL" command

Due to insufficient escaping of the special characters in the "copy as cURL" feature, an attacker could trick a user into using this command, potentially leading to local code execution on the user's system. *This bug only affects Firefox for Windows. Other versions of Firefox are unaffected.*. This vulnerability was fixed in Firefox ESR 128.10, Firefox ESR 115.23, and Thunderbird 128.10.

CVSS 3.1 · 5.7 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-4086

Specially crafted filename could be used to obscure download type

A specially crafted filename containing a large number of encoded newline characters could obscure the file's extension when displayed in the download dialog. *This bug only affects Thunderbird for Android. Other versions of Thunderbird are unaffected.*. This vulnerability was fixed in Firefox 138 and Thunderbird 138.

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

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-4089

Potential local code execution in "copy as cURL" command

Due to insufficient escaping of special characters in the "copy as cURL" feature, an attacker could trick a user into using this command, potentially leading to local code execution on the user's system. This vulnerability was fixed in Firefox 138 and Thunderbird 138.

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

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2026-2791

Mitigation bypass in the Networking: Cache component

Mitigation bypass in the Networking: Cache component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

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

Vendors

Mozilla

Products

Firefox Firefox Esr Thunderbird

CVE-2026-2788

Incorrect boundary conditions in the Audio/Video: GMP component

Incorrect boundary conditions in the Audio/Video: GMP component. This vulnerability was fixed in Firefox 148, Firefox ESR 115.33, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

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

Vendors

Mozilla

Products

Firefox Firefox Esr Thunderbird

CVE-2025-0239

Alt-Svc ALPN validation failure when redirected

When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure site. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.

CVSS 3.1 · 4 Medium EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-23108

Firefox Mobile iOS Full Address Bar Spoof Using Open in New Tab and Javascript URI

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.

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

Vendors

Mozilla

Products

Firefox

CVE-2025-23109

Address bar spoofing on iOS using long hostnames

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.

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

Vendors

Mozilla

Products

Firefox

CVE-2025-0510

Address of e-mail sender can be spoofed by malicious email

Thunderbird displayed an incorrect sender address if the From field of an email used the invalid group name syntax that is described in CVE-2024-49040. This vulnerability was fixed in Thunderbird 128.7 and Thunderbird 135.

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

Vendors

Mozilla Redhat

Products

Thunderbird Enterprise Linux Rhel Aus and 3 more

CVE-2025-1017

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

Memory safety bugs present in Firefox 134, Thunderbird 134, Firefox ESR 128.6, 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 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-2025-1020

Memory safety bugs fixed in Firefox 135 and Thunderbird 135

Memory safety bugs present in Firefox 134 and Thunderbird 134. 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 and Thunderbird 135.

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

Vendors

Mozilla

Products

Firefox Thunderbird

CVE-2025-1930

AudioIPC StreamData could trigger a use-after-free in the Browser process

On Windows, a compromised content process could use bad StreamData sent over AudioIPC to trigger a use-after-free in the Browser process. This could have led to a sandbox escape. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

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

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1931

Use-after-free in WebTransportChild

It was possible to cause a use-after-free in the content process side of a WebTransport connection, leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1932

Inconsistent comparator in XSLT sorting led to out-of-bounds access

An inconsistent comparator in xslt/txNodeSorter could have resulted in potentially exploitable out-of-bounds access. Only affected version 122 and later. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1933

JIT corruption of WASM i32 return values on 64-bit CPUs

On 64-bit CPUs, when the JIT compiles WASM i32 return values they can pick up bits from left over memory. This can potentially cause them to be treated as a different type. This vulnerability was fixed in Firefox 136, Firefox ESR 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVSS 3.1 · 7.6 High EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more

CVE-2025-1934

Unexpected GC during RegExp bailout processing

It was possible to interrupt the processing of a RegExp bailout and run additional JavaScript, potentially triggering garbage collection when the engine was not expecting it. 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-2025-1937

Memory safety bugs fixed in Firefox 136, Thunderbird 136, Firefox ESR 115.21, Firefox ESR 128.8, and Thunderbird 128.8

Memory safety bugs present in Firefox 135, Thunderbird 135, Firefox ESR 115.20, 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 115.21, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.

CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Vendors

Mozilla Redhat

Products

Firefox Thunderbird Enterprise Linux and 5 more