CVE-2026-40518
HighCVSS 7.1Exploitation Probability (EPSS)
Low risk28th percentile - higher than 28% of all known CVEs
Summary
ByteDance DeerFlow before commit 2176b2b contains a path traversal and arbitrary file write vulnerability in bootstrap-mode custom-agent creation where the agent name validation is bypassed. Attackers can supply traversal-style values or absolute paths as the agent name to influence directory creation and write files outside the intended custom-agent directory.
Risk Assessment
An attacker can write files to arbitrary locations on the filesystem, potentially leading to privilege escalation, code execution, or system integrity compromise, subject to filesystem permissions.
Recommendation
Update ByteDance DeerFlow to a version containing commit 2176b2b or later. If not possible, restrict access to the bootstrap-mode custom-agent creation feature to trusted users only.
Other vulnerabilities in ByteDance DeerFlow
See all- CVE-2026-34430High
A sandbox escape vulnerability in ByteDance DeerFlow prior to commit 92c7a20 allows attackers to bypass regex-based validation using shell features like directory changes and relative paths. This enables arbitrary command execution on the host system through subprocess invocation with shell interpretation enabled.
- CVE-2026-32859Medium
A stored cross-site scripting vulnerability in the artifacts API of ByteDance DeerFlow prior to commit 5dbb362 allows attackers to inject malicious HTML or JavaScript by uploading it as artifacts. The code executes in the browser context when users view the artifacts.
Original NVD description (English source)
ByteDance DeerFlow before commit 2176b2b contains a path traversal and arbitrary file write vulnerability in bootstrap-mode custom-agent creation where the agent name validation is bypassed. Attackers can supply traversal-style values or absolute paths as the agent name to influence directory creation and write files outside the intended custom-agent directory, potentially achieving arbitrary file write on the system subject to filesystem permissions.