Arbitrary file write via unvalidated download filename
Published Aug 9, 2025 · Updated Aug 12, 2025
Relative path traversal in Assemblyline 4 Service Client before 4.6.1.dev138 allows man-in-the-middle attackers to write local files. The download_file() path in task_handler.py joins an unvalidated server-supplied SHA-256 string directly to the tasking directory. Exploitation requires control of the service server or its client connection and permits writes only where the service process has filesystem permission.
Summary
What happened
Relative path traversal in Assemblyline 4 Service Client before 4.6.1.dev138 allows man-in-the-middle attackers to write local files. The download_file() path in task_handler.py joins an unvalidated server-supplied SHA-256 string directly to the tasking directory. Exploitation requires control of the service server or its client connection and permits writes only where the service process has filesystem permission.
The record
- CVE
- CVE-2025-55013
- Published
- Aug 9, 2025
- Updated
- Aug 12, 2025
- Vendor
- Canadian Centre for Cyber Security
- Product
- Assemblyline
- Classifications
- CWE-23, T1053.003
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 9, 2025CVE publishedPublication date reported by the CVE source.
- Aug 12, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 4.6.1.dev138
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- GHSA-75jv-vfxf-3865 path-traversal payload and exploit flowproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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