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TI-2026-23202 Aliases CVE-2026-29057GHSA-ggv3-7p47-pfv8

Next.js: HTTP request smuggling in rewrites

Priority LOW 34CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Partial Red Hat: 5 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat.

Summary

Next.js is a React framework for building full-stack web applications. Starting in version 9.5.0 and prior to versions 15.5.13 and 16.1.7, when Next.js rewrites proxy traffic to an external backend, a crafted `DELETE`/`OPTIONS` request using `Transfer-Encoding: chunked` could trigger request boundary disagreement between the proxy and backend. This could allow request smuggling through rewritten routes. An attacker could smuggle a second request to unintended backend routes (for example, internal/admin endpoints), bypassing assumptions that only the configured rewrite destination/path is reachable. This does not impact applications hosted on providers that handle rewrites at the CDN level, such as Vercel. The vulnerability originated in an upstream library vendored by Next.js. It is fixed in Next.js 15.5.13 and 16.1.7 by updating that dependency’s behavior so `content-length: 0` is added only when both `content-length` and `transfer-encoding` are absent, and `transfer-encoding` is no longer removed in that code path. If upgrading is not immediately possible, block chunked `DELETE`/`OPTIONS` requests on rewritten routes at the edge/proxy, and/or enforce authentication/authorization on backend routes.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00464 40th percentileScored 2026-11-07
Fix Partial next.js (vercel): 16.1.7, 15.5.13next (npm): 16.1.7, 15.5.13Red Hat: 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
vercelnext.js16.0.0-beta.0 to before 16.1.7; 9.5.0 to before 15.5.1316.1.7, 15.5.13Patch availableCNA
—next (npm)16.0.0-beta.0 to before 16.1.716.1.7Patch availableGHSA-ggv3-7p47-pfv8
—next (npm)9.5.0 to before 15.5.1315.5.13Patch availableGHSA-ggv3-7p47-pfv8
  • next.js Vendorvercel Affected 16.0.0-beta.0 to before 16.1.7; 9.5.0 to before 15.5.13 Fixed in 16.1.7, 15.5.13 Patch available CNA
  • next (npm) Vendor— Affected 16.0.0-beta.0 to before 16.1.7 Fixed in 16.1.7 Patch available GHSA-ggv3-7p47-pfv8
  • next (npm) Vendor— Affected 9.5.0 to before 15.5.13 Fixed in 15.5.13 Patch available GHSA-ggv3-7p47-pfv8

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*9.5.0 to before 15.5.13; 16.0.0 to before 16.1.7Vulnerablevercel
  • cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:* Versions 9.5.0 to before 15.5.13; 16.0.0 to before 16.1.7 Vulnerable ·vercel

Remediation

  • Fix · CNA next.js (vercel) Fixed in 16.1.7, 15.5.13
  • Fix · GHSA-ggv3-7p47-pfv8 next (npm) Fixed in 16.1.7 Advisory →
  • Fix · GHSA-ggv3-7p47-pfv8 next (npm) Fixed in 15.5.13 Advisory →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet: Fix deferred
Red Hat Trusted Artifact SignerAffectedNo fix yet: Fix deferred
streams for Apache Kafka 2AffectedNo fix yet: Fix deferred
streams for Apache Kafka 3AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-29057
  2. 2026-10-03 Alias added: GHSA-ggv3-7p47-pfv8

References

Patch 1

Advisory 2

Other 3

  • 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
See all 62 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences