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CVE-2026-40518

critical

ByteDance DeerFlow before commit 2176b2b contains a path traversal and arbitrary file write vulnerability in bootstrap-mode custom-agent creation where the age…

Vendor / product: Bytedance — deerflow

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.

CVSS
9.1
9.1 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Severity source: NVD CVSS v3.1 (nvd@nist.gov)
Timeline (UTC)
Published: 2026-04-17 17:17
Modified: 2026-10-26 21:10
NVD status: Analyzed
Last synced 2 days ago
Verified against the source API 2026-10-27 07:07 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

bytedance / deerflow 2.0-m0

Weakness classification (CWE)

CWE-22

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Patch / mitigation: https://github.com/bytedance/deer-flow/commit/2176b2bbfccfce25ceee08318813f96d843a13fd
Patch / mitigation: https://github.com/bytedance/deer-flow/pull/2274

References

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 07:07 UTC · record ↗

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