---
id: CVE-2026-108258
title: >-
  Shiny for Python is a framework for building interactive web applications in
  Python
summary: >-
  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
  validati…
severity: medium
cvss: 6.9
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-22
vendor: shiny
product: shiny
affected:
  - 'shiny >= 1.4.0, <= 1.6.3'
patched:
  - shiny 1.6.4
published: '2026-10-09'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T17:25:57.940'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-108258'
references:
  - url: >-
      https://github.com/posit-dev/py-shiny/commit/1d8ecb46cbc9621b7dc8812111d26692e086b376
    label: security-advisories@github.com
  - url: 'https://github.com/posit-dev/py-shiny/releases/tag/v1.6.4'
    label: security-advisories@github.com
  - url: >-
      https://github.com/posit-dev/py-shiny/security/advisories/GHSA-47c3-hpmg-7j6p
    label: security-advisories@github.com
  - url: 'https://github.com/advisories/GHSA-47c3-hpmg-7j6p'
  - url: 'https://github.com/posit-dev/py-shiny'
  - url: 'https://pypi.org/project/shiny'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-108258'
tags:
  - nvd
  - ghsa
  - pip
  - osv
  - cve.org
epss: 0.00358
epssPercentile: 0.29344
aliases:
  - GHSA-47c3-hpmg-7j6p
  - PYSEC-2026-4300
ecosystem: pip
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-10-13T18:33:09.230741Z'
cvssSource: cna
ingestedAt: '2026-10-09T21:12:42.323Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-108258)

Affected packages:

- `shiny >= 1.4.0, <= 1.6.3`

Patched in:

- `shiny 1.6.4`

Source: https://github.com/advisories/GHSA-47c3-hpmg-7j6p