9.1
/ 10
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Description
React Router is a router for React. In @react-router/node versions 7.0.0 through 7.9.3, @remix-run/deno prior to version 2.17.2, and @remix-run/node prior to version 2.17.2, if createFileSessionStorage() is being used from @react-router/node (or @remix-run/node/@remix-run/deno in Remix v2) with an unsigned cookie, it is possible for an attacker to cause the session to try to read/write from a location outside the specified session file directory. The success of the attack would depend on the permissions of the web server process to access those files. Read files cannot be returned directly to the attacker. Session file reads would only succeed if the file matched the expected session file format. If the file matched the session file format, the data would be populated into the server side session but not directly returned to the attacker unless the application logic returned specific session information. This issue has been patched in @react-router/node version 7.9.4, @remix-run/deno version 2.17.2, and @remix-run/node version 2.17.2.
AI Analysis
Path Traversal vulnerability in React Router's File Session Storage
Basic Information
ID
CVE-2025-61686
Source
GitHub_M
Published
Jan 10, 2026 at 02:41
Affected Product
Vendor
remix-run
Product
react-router
Version
@react-router/node >= 7.0.0, < 7.9.4
Affected Versions
remix-run react-router @react-router/node >= 7.0.0, < 7.9.4
remix-run react-router @remix-run/deno < 2.17.2
remix-run react-router @remix-run/node < 2.17.2
remix-run react-router @remix-run/deno < 2.17.2
remix-run react-router @remix-run/node < 2.17.2
CWE Classification
AI Assessment
AI Score
9.1 / 10
AI Severity
Critical
Vendor
Remix-run
Product
React Router
Version
@react-router/node 7.0.0-7.9.3, @remix-run/deno 2.17.2, @remix-run/node 2.17.2