CVE-2026-86258
nbviewer through 1.0.1 contains a path traversal vulnerability in LocalFileHandler.can_show() that uses string-prefix comparison instead of proper path validation. Attackers can read files from sibling directories outside the configured root by requesting paths that share the root as a textual prefix, disclosing unintended notebooks and credentials.
Published:Sep 6, 2026
Last Modified:Sep 7, 2026
EPS:Sep 6, 2026
EPSS Score:
CVSS Score:5.9
Affected Products
Vendor
Product
Action
Vendor
Jupyter
Product
Nbviewer
Jupyter
Nbviewer
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
References
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
