CybercentreCanada assemblyline up to 4.6.1.dev137 task_handler.py path traversal

Summaryinfo

A vulnerability labeled as critical has been found in CybercentreCanada assemblyline up to 4.6.1.dev137. Affected by this vulnerability is an unknown functionality of the file task_handler.py. The manipulation results in path traversal. This vulnerability was named CVE-2025-55013. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in CybercentreCanada assemblyline up to 4.6.1.dev137. It has been classified as critical. Affected is an unknown part of the file task_handler.py. The manipulation with an unknown input leads to a path traversal vulnerability. CWE is classifying the issue as CWE-23. The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory. This is going to have an impact on integrity, and availability. CVE summarizes:

The Assemblyline 4 Service Client interfaces with the API to fetch tasks and publish the result for a service in Assemblyline 4. In versions below 4.6.1.dev138, the Assemblyline 4 Service Client (task_handler.py) accepts a SHA-256 value returned by the service server and uses it directly as a local file name.A malicious or compromised server (or any MITM that can speak to client) can return a path-traversal payload such as `../../../etc/cron.d/evil` and force the client to write the downloaded bytes to an arbitrary location on disk. This is fixed in version 4.6.1.dev138.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2025-55013 since 08/04/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1006.

Upgrading to version 4.6.1.dev138 eliminates this vulnerability. Applying the patch 351414e7e96cc1f5640ae71ae51b939e8ba30900 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-24028). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• CybercentreCanada

Name

• assemblyline

Version

• 4.6.1.dev137

License

• open-source

Website

• Product: https://github.com/CybercentreCanada/assemblyline/

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Once again VulDB remains the best source for vulnerability data.

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