CVE-2026-108258
Received
Received - Intake
Path Traversal in Shiny for Python
Vulnerability report for CVE-2026-108258, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-10-09
Last updated on: 2026-10-09
Assigner: GitHub, Inc.
Description
Description
Shiny for Python is a framework for building interactive web applications in Python. From 1.4.0 until 1.6.4, bookmark restore accepts a client-supplied state_id and joins it into the server-side shiny_bookmarks directory without validating that it is a single safe path segment. An unauthenticated request can use parent-directory segments or an absolute path to make the server open input.json and values.json outside the bookmark store, even when bookmark_store is set to disable. In applications configured with bookmark_store set to server and using ui.input_file(), the restore handler can additionally copy and expose an attacker-selected file from an attacker-selected directory. This issue is fixed in version 1.6.4.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| posit-dev | py-shiny | >= 1.4.0, < 1.6.4 |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-22 | The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory. |
