CVE-2026-40518
Full vulnerability record from the local CVENow database.
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.
Severity
HIGH
CVSS score
7.1
(v4.0)
Vulnerability status
Analyzed
Source identifier
Published
2026-04-17 17:17:09.543000
Last modified
2026-10-26 21:10:00.170000
View original CVE JSON
{
"id": "CVE-2026-40518",
"sourceIdentifier": "[email protected]",
"published": "2026-04-17T17:17:09.543",
"lastModified": "2026-10-26T21:10:00.170",
"vulnStatus": "Analyzed",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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."
},
{
"lang": "es",
"value": "ByteDance DeerFlow antes del commit 2176b2b contiene una vulnerabilidad de salto de ruta y escritura arbitraria de archivos en la creación de agentes personalizados en modo bootstrap, donde se omite la validación del nombre del agente. Los atacantes pueden proporcionar valores de estilo de salto de ruta o rutas absolutas como nombre del agente para influir en la creación de directorios y escribir archivos fuera del directorio de agentes personalizados previsto, logrando potencialmente la escritura arbitraria de archivos en el sistema sujeta a los permisos del sistema de archivos."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "bytedance",
"product": "deer-flow",
"defaultStatus": "unaffected",
"repo": "https://github.com/bytedance/deer-flow",
"packageURL": "pkg:github/bytedance/deer-flow",
"versions": [
{
"version": "0",
"lessThan": "2176b2bbfccfce25ceee08318813f96d843a13fd",
"versionType": "git",
"status": "affected"
}
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"metrics": {
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"source": "[email protected]",
"type": "Secondary",
"cvssData": {
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"attackRequirements": "NONE",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"vulnConfidentialityImpact": "NONE",
"vulnIntegrityImpact": "HIGH",
"vulnAvailabilityImpact": "LOW",
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"subAvailabilityImpact": "NONE",
"exploitMaturity": "NOT_DEFINED",
"confidentialityRequirement": "NOT_DEFINED",
"integrityRequirement": "NOT_DEFINED",
"availabilityRequirement": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
"modifiedVulnIntegrityImpact": "NOT_DEFINED",
"modifiedVulnAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"Safety": "NOT_DEFINED",
"Automatable": "NOT_DEFINED",
"Recovery": "NOT_DEFINED",
"valueDensity": "NOT_DEFINED",
"vulnerabilityResponseEffort": "NOT_DEFINED",
"providerUrgency": "NOT_DEFINED"
}
}
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"cvssMetricV31": [
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},
{
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"type": "Primary",
"cvssData": {
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"ssvcV203": [
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"timestamp": "2026-04-17T18:35:29.825676Z",
"id": "CVE-2026-40518",
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{
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"role": "CISA Coordinator",
"version": "2.0.3"
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"weaknesses": [
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"source": "[email protected]",
"type": "Secondary",
"description": [
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"value": "CWE-22"
}
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"configurations": [
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"references": [
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"source": "[email protected]",
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{
"url": "https://github.com/bytedance/deer-flow/pull/2274",
"source": "[email protected]",
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},
{
"url": "https://www.vulncheck.com/advisories/bytedance-deerflow-path-traversal-and-arbitrary-file-write-via-bootstrap-mode",
"source": "[email protected]",
"tags": [
"Third Party Advisory"
]
}
]
}