Where
-Infinity
0
Severity
7

Security Vulnerabilities fixed in Thunderbird 128.11.1

First published (updated )
Advisory
MFSA2025-49
Severity
7

Security Vulnerabilities fixed in Thunderbird 139.0.2

First published (updated )
Advisory
MFSA2025-50
Severity
4

Memory safety bug present in Firefox ESR 128.10, and Thunderbird 128.10. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.11.

First published (updated )
Severity
4

Memory safety bugs present in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. 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 affects Firefox < 139 and Firefox ESR < 128.11.

First published (updated )
Severity
7.5
Double Free
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A double-free could have occurred in vpxcodecencinitmulti after a failed allocation when initializing the encoder for WebRTC. This could have caused memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 139 and Thunderbird < 128.11.

1 / 2
Source: MITRE
First published (updated )
Severity
9

Security Vulnerabilities fixed in Thunderbird 128.10.2

First published (updated )
Advisory
MFSA2025-40
Severity
9

Security Vulnerabilities fixed in Thunderbird 138.0.2

First published (updated )
Advisory
MFSA2025-41
Severity
1

It was possible to craft an email that showed a tracking link as an attachment. If the user attempted to open the attachment, Thunderbird automatically accessed the link. The configuration to block remote content did not prevent that. Thunderbird has been fixed to no longer allow access to web pages listed in the X-Mozilla-External-Attachment-URL header of an email. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.

First published (updated )
Severity
7

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 as the actual address. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.

First published (updated )
Severity
7

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.

First published (updated )

A crafted HTML email using mailbox:/// links can trigger automatic, unsolicited downloads of .pdf files to the user's desktop or home directory without prompting, even if auto-saving is disabled. This behavior can be abused to fill the disk with garbage data (e.g. using /dev/urandom on Linux) or to leak Windows credentials via SMB links when the email is viewed in HTML mode. While user interaction is required to download the .pdf file, visual obfuscation can conceal the download trigger. Viewing the email in HTML mode is enough to load external content. This vulnerability affects Thunderbird < 128.10.1 and Thunderbird < 138.0.1.

First published (updated )
Severity
7

Security Vulnerabilities fixed in Thunderbird 128.10.1

First published (updated )
Advisory
MFSA2025-34

Infoleak

Risk 33
Severity
7
Infoleak

A crafted HTML email using mailbox:/// links can trigger automatic, unsolicited downloads of .pdf files to the user's desktop or home directory without prompting, even if auto-saving is disabled. This behavior can be abused to fill the disk with garbage data (e.g. using /dev/urandom on Linux) or to leak Windows credentials via SMB links when the email is viewed in HTML mode. While user interaction is required to download the .pdf file, visual obfuscation can conceal the download trigger. Viewing the email in HTML mode is enough to load external content.

1 / 3
Source: Mozilla
First published (updated )
Severity
7

Security Vulnerabilities fixed in Thunderbird 138.0.1

First published (updated )
Advisory
MFSA2025-35

Infoleak

Risk 33
Severity
7
Infoleak

A crafted HTML email using mailbox:/// links can trigger automatic, unsolicited downloads of .pdf files to the user's desktop or home directory without prompting, even if auto-saving is disabled. This behavior can be abused to fill the disk with garbage data (e.g. using /dev/urandom on Linux) or to leak Windows credentials via SMB links when the email is viewed in HTML mode. While user interaction is required to download the .pdf file, visual obfuscation can conceal the download trigger. Viewing the email in HTML mode is enough to load external content.

1 / 3
Source: Mozilla
First published (updated )
Severity
7

Mozilla Firefox's update mechanism allowed a medium-integrity user process to interfere with the SYSTEM-level updater by manipulating the file-locking behavior. By injecting code into the user-privileged process, an attacker could bypass intended access controls, allowing SYSTEM-level file operations on paths controlled by a non-privileged user and enabling privilege escalation. This vulnerability affects Firefox < 138, Firefox ESR < 128.10, Firefox ESR < 115.23, Thunderbird < 138, and Thunderbird ESR < 128.10.

First published (updated )
Severity
4

Memory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. 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 affects Firefox < 138, Firefox ESR < 128.10, Thunderbird < 138, and Thunderbird ESR < 128.10.

First published (updated )
Severity
7

A process isolation vulnerability in Firefox stemmed from improper handling of javascript: URIs, which could allow content to execute in the top-level document's process instead of the intended frame, potentially enabling a sandbox escape. This vulnerability affects Firefox < 138, Firefox ESR < 128.10, Firefox ESR < 115.23, Thunderbird < 138, and Thunderbird ESR < 128.10.

First published (updated )
Severity
7

Memory safety bug present in Firefox ESR 128.9, and Thunderbird 128.9. This bug showed evidence of memory corruption and we presume that with enough effort this could have been exploited to run arbitrary code. This vulnerability affects Firefox ESR < 128.10 and Thunderbird ESR < 128.10.

First published (updated )
Severity
4

A vulnerability was identified in Firefox where XPath parsing could trigger undefined behavior due to missing null checks during attribute access. This could lead to out-of-bounds read access and potentially, memory corruption. This vulnerability affects Firefox < 138, Firefox ESR < 128.10, Thunderbird < 138, and Thunderbird ESR < 128.10.

First published (updated )
Severity
4

A security vulnerability in Firefox allowed malicious sites to use redirects to send credentialed requests to arbitrary endpoints on any site that had invoked the Storage Access API. This enabled potential Cross-Site Request Forgery attacks across origins.

1 / 2
Source: Mozilla
First published (updated )
Severity
4

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.

First published (updated )
Severity
4

An attacker with control over a content process could potentially leverage the privileged UITour actor to leak sensitive information or escalate privileges.

First published (updated )
Severity
7

Memory safety bugs present in Firefox 137 and Thunderbird 137. 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.

First published (updated )
Severity
1

A vulnerability existed in Firefox for Android where potentially sensitive library locations were logged via Logcat.

1 / 2
Source: Mozilla
First published (updated )
Severity
7

Security Vulnerabilities fixed in Thunderbird 128.10

First published (updated )
Advisory
MFSA2025-32
Severity
4

Memory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. 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.

First published (updated )
Severity
7

Modification of specific WebGL shader attributes could trigger an out-of-bounds read, which, when chained with other vulnerabilities, could be used to escalate privileges.This bug only affects Firefox for macOS. Other versions of Firefox are unaffected.

1 / 2
Source: Mozilla
First published (updated )
Severity
4

A vulnerability was identified in Firefox where XPath parsing could trigger undefined behavior due to missing null checks during attribute access. This could lead to out-of-bounds read access and potentially, memory corruption.

1 / 2
Source: Mozilla
First published (updated )
Severity
7

A process isolation vulnerability in Firefox stemmed from improper handling of javascript: URIs, which could allow content to execute in the top-level document's process instead of the intended frame, potentially enabling a sandbox escape.

1 / 3
Source: Mozilla
First published (updated )
Severity
4

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 Firefox for Android. Other versions of Firefox are unaffected.

1 / 2
Source: Mozilla
First published (updated )

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