REDHAT-BUG-2366291: Thunderbird vulnerability

Published May 14, 2025
·
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.

Affected Software

1 affected component
Mozilla Thunderbird<128.10.1, <138.0.1

Event History

May 14, 2025
Data Sourced
via Red Hat·06:01 PM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2366291?

The severity of REDHAT-BUG-2366291 is considered high due to the potential for unsolicited file downloads.

2

How do I fix REDHAT-BUG-2366291?

To fix REDHAT-BUG-2366291, ensure that you update Mozilla Thunderbird to the latest version that addresses this vulnerability.

3

What is the impact of REDHAT-BUG-2366291?

The impact of REDHAT-BUG-2366291 can include unwarranted downloads of large files that may fill up disk space.

4

Can REDHAT-BUG-2366291 be exploited remotely?

Yes, REDHAT-BUG-2366291 can be exploited remotely through crafted HTML emails.

5

Is there a workaround for REDHAT-BUG-2366291?

A possible workaround for REDHAT-BUG-2366291 is to avoid opening HTML emails from untrusted sources.

Contact

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