CVE-2026-40518
Path Traversal and Arbitrary File Write in ByteDance DeerFlow Agent
Publication date: 2026-04-17
Last updated on: 2026-04-17
Assigner: VulnCheck
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| bytedance | deerflow | * |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-22 | The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability exists in ByteDance DeerFlow before commit 2176b2b and involves a path traversal and arbitrary file write issue during the bootstrap-mode custom-agent creation process.
The problem arises because the validation of the agent name can be bypassed, allowing attackers to supply traversal-style values or absolute paths as the agent name.
This manipulation influences directory creation and enables writing files outside the intended custom-agent directory.
As a result, attackers may achieve arbitrary file write on the system, subject to filesystem permissions.
How can this vulnerability impact me? :
This vulnerability can allow an attacker with limited privileges to write files anywhere on the filesystem where the application has write permissions.
Such arbitrary file write can lead to serious impacts including the possibility of executing malicious code, modifying or deleting important files, or disrupting system operations.
The overall impact depends on the filesystem permissions and the environment in which ByteDance DeerFlow is running.