Critical Security Flaws in Thunderbird: User Interface Misrepresentation and Information Disclosure
Summary
RLSA-2025:7435: Important: thunderbird security update. Affects thunderbird versions < 0:128.10.0-1.el9_5. Fixed in 0:128.10.0-1.el9_5. How to fix ↓
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Background
Mozilla Thunderbird is a standalone mail and newsgroup client that allows users to manage their emails and news feeds efficiently. It is known for its robust features, including customizable interfaces, advanced search capabilities, and support for multiple accounts. However, recent vulnerabilities have exposed users to risks such as information disclosure and UI misrepresentation, which can compromise user data and privacy.
Vulnerability Detail
The vulnerabilities identified in Thunderbird include: CVE-2025-3523, which involves User Interface (UI) Misrepresentation of attachment URLs, potentially misleading users about the nature of attachments. CVE-2025-2830 allows for Information Disclosure of the /tmp directory listing, which can expose sensitive data. CVE-2025-3522 leaks hashed Window credentials via crafted attachment URLs, posing a significant security risk. These vulnerabilities can lead to unauthorized access to sensitive information and compromise user privacy.
How To Fix
Minimum fixed version
0:128.10.0-1.el9_5
This is the first release that contains the fix.
sudo dnf update thunderbirdTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, users are advised to avoid opening attachments from untrusted sources and to verify the authenticity of any URLs before clicking on them.
Conclusion
The identified vulnerabilities in Thunderbird pose significant risks to user data and privacy. It is crucial for users to update their software to the latest patched version to mitigate these risks. Additionally, exercising caution when handling attachments and URLs can help protect against potential exploitation.
See every vulnerability recorded for thunderbird →
FAQ
The main vulnerabilities include UI misrepresentation, information disclosure of the /tmp directory, and leakage of hashed Window credentials via crafted attachment URLs.
You can check your version of Thunderbird by navigating to the 'Help' menu and selecting 'About Thunderbird'. Compare it with the patched version 0:128.10.0-1.el9_5.
If you cannot update immediately, avoid opening suspicious attachments and verify URLs before interacting with them.
The CVSS score for these vulnerabilities is 7.4, indicating a high severity level.
Vulert allows you to monitor and alert in real-time for open-source vulnerabilities using a manifest file like package-lock.json. You can check if your application is affected by visiting the Vulert playground at Vulert Scanner.
References
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