react-router: Improper Limitation of a Pathname to a Restricted Directory
CVE-2025-61686 is a critical-severity improper limitation of a pathname to a restricted directory vulnerability in react-router from Remix-run, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected react-router versions: @react-router/node >= 7.0.0, < 7.9.4; @remix-run/deno < 2.17.2; @remix-run/node < 2.17.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 17.3% chance of exploitation within 30 days, which is in the top 2.84% of all scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update React-router/node to 7.9.4 or a later version.
- Update Remix-run/deno to 2.17.2 or a later version.
- Update Remix-run/node to 2.17.2 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Remix-run | react-router | @react-router/node >= 7.0.0, < 7.9.4; @remix-run/deno < 2.17.2; @remix-run/node < 2.17.2 | Not stated |
| Red Hat | Cryostat 4 | Not specified in the record | Not stated |
| Red Hat | Gatekeeper 3 | Not specified in the record | Not stated |
| Red Hat | Logging Subsystem for Red Hat OpenShift | Not specified in the record | Not stated |
| Red Hat | Migration Toolkit for Applications 7 | Not specified in the record | Not stated |
| Red Hat | Migration Toolkit for Applications 8 | Not specified in the record | Not stated |
| Red Hat | Migration Toolkit for Containers | Not specified in the record | Not stated |
| Red Hat | Migration Toolkit for Virtualization | Not specified in the record | Not stated |
| Red Hat | Multicluster Engine for Kubernetes | Not specified in the record | Not stated |
| Red Hat | Network Observability Operator | Not specified in the record | Not stated |
| Red Hat | Node HealthCheck Operator | Not specified in the record | Not stated |
| Red Hat | OpenShift Lightspeed | Not specified in the record | Not stated |
| Red Hat | OpenShift Pipelines | Not specified in the record | Not stated |
| Red Hat | OpenShift Service Mesh 2 | Not specified in the record | Not stated |
| Red Hat | OpenShift Service Mesh 3 | Not specified in the record | Not stated |
| Red Hat | Red Hat Advanced Cluster Management for Kubernetes 2 | Not specified in the record | Not stated |
| Red Hat | Red Hat Advanced Cluster Security 4 | Not specified in the record | Not stated |
| Red Hat | Red Hat Ansible Automation Platform 2 | Not specified in the record | Not stated |
| Red Hat | Red Hat build of Apache Camel - HawtIO 4 | Not specified in the record | Not stated |
| Red Hat | Red Hat build of Apicurio Registry 2 | Not specified in the record | Not stated |
| Red Hat | Red Hat Build of Kueue | Not specified in the record | Not stated |
| Red Hat | Red Hat build of OptaPlanner 8 | Not specified in the record | Not stated |
| Red Hat | Red Hat Connectivity Link 1 | Not specified in the record | Not stated |
| Red Hat | Red Hat Data Grid 8 | Not specified in the record | Not stated |
| Red Hat | Red Hat Developer Hub | Not specified in the record | Not stated |
Version data comes from the organisation that assigned the CVE; 25 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H. Scored by CNA (github.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.1 | Critical | CNA (github.com) |
| CVSS 3.1 | 9.1 | Critical | CNA |
Official 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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory
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.
How developers prevent this class of flaw
- For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/remix-run/react-router/security/advisories/GHSA-9583-h5hc-x8cwThird Party Advisory
Other references
Other vulnerabilities in react-router
- 7.5 High severity
- 7.5 High severity
- 8.1 High severity
- 7.5 High severity
- 8.2 High severity
- 7.6 High severity
Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities
- 9.8 Critical severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.5 High severity
- 7.5 High severity
- 8.8 High severity
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