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.
https://github.com/posit-dev/py-shiny/security/advisories/GHSA-47c3-hpmg-7j6p
https://github.com/posit-dev/py-shiny/releases/tag/v1.6.4
https://github.com/posit-dev/py-shiny/commit/1d8ecb46cbc9621b7dc8812111d26692e086b376
Published: 2026-10-09
Updated: 2026-10-09
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N
Severity: Medium
Base Score: 5.3
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Severity: Medium
Base Score: 6.9
Vector: 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
Severity: Medium