CVE-2025-30218
Next.js is a React framework for building full-stack web applications. To mitigate CVE-2025-29927, Next.js validated the x-middleware-subrequest-id which persisted across multiple incoming requests. However, this subrequest ID is sent to all requests, even if the destination is not the same host as the Next.js application. Initiating a fetch request to a third-party within Middleware will send the x-middleware-subrequest-id to that third party. This vulnerability is fixed in 12.3.6, 13.5.10, 14.2.26, and 15.2.4.
| Software | From | Fixed in |
|---|---|---|
next
|
12.3.5 | 12.3.5.x |
|
next
|
12.3.5 | 12.3.6 |
|
next
|
13.5.9 | 13.5.9.x |
|
next
|
13.5.9 | 13.5.10 |
|
next
|
14.2.25 | 14.2.25.x |
|
next
|
14.2.25 | 14.2.26 |
|
next
|
15.2.3 | 15.2.3.x |
|
next
|
15.2.3 | 15.2.4 |
| vercel / next.js | 12.3.5 | 12.3.5.x |
| vercel / next.js | 13.5.9 | 13.5.9.x |
| vercel / next.js | 14.2.25 | 14.2.25.x |
| vercel / next.js | 15.2.3 | 15.2.3.x |
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