CVE-2025-31137

HIGHCVSS 7.5/10EPSS 1.13%

Last modified

CVE-2025-31137 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. React Router is a multi-strategy router for React bridging the gap from React 18 to React 19. There is a vulnerability in Remix/React Router that affects all Remix 2 and React Router 7 consumers using the Express adapter. EPSS estimates a 1.13% chance of exploitation in the next 30 days.

Description

React Router is a multi-strategy router for React bridging the gap from React 18 to React 19. There is a vulnerability in Remix/React Router that affects all Remix 2 and React Router 7 consumers using the Express adapter. Basically, this vulnerability allows anyone to spoof the URL used in an incoming Request by putting a URL pathname in the port section of a URL that is part of a Host or X-Forwarded-Host header sent to a Remix/React Router request handler. This issue has been patched and released in Remix 2.16.3 and React Router 7.4.1.

Metrics

CVSS 3.0
7.5/10

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability
1.13%

62.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published
Last Modified
Status
Deferred

Frequently Asked Questions

What is CVE-2025-31137?
React Router is a multi-strategy router for React bridging the gap from React 18 to React 19. There is a vulnerability in Remix/React Router that affects all Remix 2 and React Router 7 consumers using the Express adapter. Basically, this vulnerability allows anyone to spoof the URL used in an incoming Request by putting a URL pathname in the port section of a URL that is part of a Host or X-Forwarded-Host header sent to a Remix/React Router request handler. This issue has been patched and released in Remix 2.16.3 and React Router 7.4.1.
How severe is CVE-2025-31137?
CVE-2025-31137 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.13% probability of exploitation in the next 30 days.
How do I fix CVE-2025-31137?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-31137?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST