Is CVE-2026-40518 actively exploited?

No active exploitation of CVE-2026-40518 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-40518 be exploited remotely?

Yes. CVE-2026-40518 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-40518?

CVE-2026-40518 has a CVSS score of 7.1 (HIGH).

HOME VULNERABILITIESCVE-2026-40518

HIGH

CVE-2026-40518

CWE-22Published: April 17, 2026· Updated: Apr 17, 2026

7.1

CVSS v3.1

EPSS:0.03%probability of exploitation in 30 daysPercentile:7.6th

Official Description

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.

NVD Source

Technical Analysis

CVE-2026-40518 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.1.