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CVE-2026-40518

ByteDance DeerFlow Path Traversal and Arbitrary File Write via Bootstrap Mode

Published: Apr 17, 2026Updated: Apr 17, 2026 Sources: CVE List NVD
NVD MITRE
7.1CVSS
HIGH

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.

EPSS Score
N/A
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available

CVSS Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:NI:LA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:HAvailability
High

Weaknesses

CWE-22

Affected Products

deer-flow
bytedance

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://github.com/bytedance/deer-flow/commit/2176b2bbfccfce25ceee08318813f96d843a13fd
github.com
https://github.com/bytedance/deer-flow/pull/2274
github.com
https://www.vulncheck.com/advisories/bytedance-deerflow-path-traversal-and-arbitrary-file-write-via-bootstrap-mode
vulncheck.com

Timeline

Published
Apr 17, 2026
Last Updated
Apr 17, 2026

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