CVE-2026-39377

Summary

The nbconvert tool, jupyter nbconvert, converts Jupyter notebooks to various other formats via Jinja templates. Versions 6.5 through 7.17.0 allow arbitrary file writes to locations outside the intended output directory when processing notebooks containing crafted cell attachment filenames. The ExtractAttachmentsPreprocessor passes attachment filenames directly to the filesystem without sanitization, enabling path traversal attacks. This vulnerability provides complete control over both the destination path and file extension. Version 7.17.1 contains a patch.

Affected Software

VendorProductVersion RangeStatus
jupyternbconvert>= 6.5, < 7.17.1affected

Weaknesses

  • CWE-22: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
  • CWE-73: CWE-73: External Control of File Name or Path

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References