Path Traversal in shiny (CVE-2026-108258)
Summary
Path traversal in shiny (CVE-2026-108258). Risk of unauthorized operations or information disclosure. Exploitable via _state_id_. Mitigation: upgrade to 1.6.4 or later.
Original description
The description as published by the source.
Impact
Shiny for Python's bookmark-restore path accepted a client-supplied _state_id_
query-string value and joined it into the server-side bookmark directory
(/shiny_bookmarks/) without validating it. A value containing ..
path segments, or an absolute path, could therefore cause the server to open and
parse input.json and values.json from a directory outside the bookmark store.
On a default application the restore was attempted whenever the client supplied a
URL query string — including when bookmarking was disabled
(bookmark_store="disable") — so no opt-in configuration was required. For such
applications the impact is an unauthenticated, server-side probe for the
existence and JSON-validity of attacker-chosen paths, constrained to those two
file names.
Applications configured with bookmark_store="server" and using
ui.input_file() are affected more seriously. The file-input restore handler
copies files out of the restore directory, so the contents of an
attacker-selected file name within an attacker-selected directory could be read
into the application.
Affected versions
1.4.0 through 1.6.3. Bookmarking was introduced in 1.4.0; earlier releases do
not contain the affected code path and are not affected.
Patches
Fixed in 1.6.4. Upgrade with:
pip install --upgrade shiny
The fix validates bookmark IDs against an allowlist — a single path segment
matching [A-Za-z0-9_-]+, which cannot express a path separator, a .. parent…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-108258 has been found in shiny.
Attackers can target a specific entry point like _state_id_ over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade shiny to 1.6.4 or later.
If unsure, ask your IT team or search "shiny CVE-2026-108258" on the vendor's site.
CVE-2026-108258 (shiny) — CWE-22
Attack surface: _state_id_ / bookmark_store
Patched: 1.6.4 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Path traversal (CWE-22) exists in shiny. Attackers reach the vulnerable code path via _state_id_.
Check the vendor advisory for the affected versions of shiny. Attack surface: _state_id_ / bookmark_store.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 1.6.4.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'shiny' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'shiny' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
shinyを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade shiny to 1.6.4ステージング環境で 1.6.4 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。