Next.js Vulnerable to HTTP Request Smuggling
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub.
Summary
Next.js is a React framework that can provide building blocks to create web applications. Prior to 13.5.1, an inconsistent interpretation of a crafted HTTP request meant that requests are treated as both a single request, and two separate requests by Next.js, leading to desynchronized responses. This led to a response queue poisoning vulnerability in the affected Next.js versions. For a request to be exploitable, the affected route also had to be making use of the [rewrites](https://nextjs.org/docs/app/api-reference/next-config-js/rewrites) feature in Next.js. The vulnerability is resolved in Next.js `13.5.1` and newer.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| vercel | next.js | 13.4.0 to before 13.5.1 | 13.5.1 | Patch available | CNA |
| — | next (npm) | 13.4.0 to before 13.5.1 | 13.5.1 | Patch available | GHSA-77r5-gw3j-2mpf |
- next.js Vendorvercel Affected 13.4.0 to before 13.5.1 Fixed in 13.5.1 Patch available CNA
- next (npm) Vendor— Affected 13.4.0 to before 13.5.1 Fixed in 13.5.1 Patch available GHSA-77r5-gw3j-2mpf
Remediation
- Fix · CNA next.js (vercel) Fixed in 13.5.1
- Fix · GHSA-77r5-gw3j-2mpf next (npm) Fixed in 13.5.1 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2024-34350
- 2026-10-03 Alias added: GHSA-77r5-gw3j-2mpf
References
Advisory 2
More vercel Next.js vulnerabilities
- TI-2025-34861 Deserialization of untrusted data in Meta react-server-dom-webpack KEVCVSS 3.1CRITICAL 10.0
- TI-2025-21309 Authorization Bypass in Next.js Middleware CVSS 3.1CRITICAL 9.1
- TI-2025-34863 Deserialization of untrusted data in Meta react-server-dom-webpack CVSS 3.1HIGH 7.5
- TI-2024-31371 Cache Poisoning in next.js CVSS 3.1HIGH 7.5
- TI-2023-24914 Next.js before 13.4.20-canary.13 lacks a cache-control header and thus empty prefetch… CVSS 3.1HIGH 7.5
- TI-2026-32490 Next.js: Server-side request forgery in applications using WebSocket upgrades CVSS 3.1HIGH 8.6
Sources
- CVE-2024-34350 · CVE Program
- CVE-2024-34350 · NVD
- FIRST EPSS
- GHSA-77r5-gw3j-2mpf · GitHub Advisory Database · CC BY 4.0
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