CVE-2026-91771

Weights & Biases wandb before 0.29.0 fails to validate the file name from server responses in the File.download function, allowing path traversal attacks. Attackers controlling the backend can supply file names with directory traversal sequences to write files outside the intended download directory, potentially enabling code execution through modification of shell startup files or Python import paths.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/wandb/wandb
https://github.com/wandb/wandb/blob/v0.27.2/wandb/apis/public/files.py#L319-L347
https://github.com/wandb/wandb/commit/e52558f3a6a94ea816af74969a13a35e5904cad6
https://github.com/wandb/wandb/issues/12592
https://github.com/wandb/wandb/releases/tag/v0.29.0
https://www.vulncheck.com/advisories/weights-biases-wandb-before-0.29.0-path-traversal-via-file-download

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 02:16

Updated : 2026-09-15 02:16

NVD link : CVE-2026-91771

Mitre link : CVE-2026-91771

CVE.ORG link : CVE-2026-91771

JSON object : View

Products Affected

No product.

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

{"id": "CVE-2026-91771", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "disclosure@vulncheck.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.8, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "REQUIRED", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.8}], "cvssMetricV40": [{"type": "Secondary", "source": "disclosure@vulncheck.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 8.7, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "HIGH", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "PASSIVE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "HIGH", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "HIGH", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "disclosure@vulncheck.com", "affectedData": [{"vendor": "wandb", "product": "wandb", "versions": [{"status": "affected", "version": "0", "lessThan": "0.29.0", "versionType": "semver"}], "packageURL": "pkg:pypi/wandb", "defaultStatus": "unaffected"}]}], "published": "2026-09-15T02:16:49.680", "references": [{"url": "https://github.com/wandb/wandb", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/wandb/wandb/blob/v0.27.2/wandb/apis/public/files.py#L319-L347", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/wandb/wandb/commit/e52558f3a6a94ea816af74969a13a35e5904cad6", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/wandb/wandb/issues/12592", "source": "disclosure@vulncheck.com"}, {"url": "https://github.com/wandb/wandb/releases/tag/v0.29.0", "source": "disclosure@vulncheck.com"}, {"url": "https://www.vulncheck.com/advisories/weights-biases-wandb-before-0.29.0-path-traversal-via-file-download", "source": "disclosure@vulncheck.com"}], "vulnStatus": "Received", "weaknesses": [{"type": "Primary", "source": "disclosure@vulncheck.com", "description": [{"lang": "en", "value": "CWE-22"}]}], "descriptions": [{"lang": "en", "value": "Weights & Biases wandb before 0.29.0 fails to validate the file name from server responses in the File.download function, allowing path traversal attacks. Attackers controlling the backend can supply file names with directory traversal sequences to write files outside the intended download directory, potentially enabling code execution through modification of shell startup files or Python import paths."}], "lastModified": "2026-09-15T02:16:49.680", "sourceIdentifier": "disclosure@vulncheck.com"}