GHSA-39w2-rjm5-chcv CVE-2026-94486
Next.js has information disclosure in development server's Model Context Protocol endpoint
- Severity
- 0.0 / 10
- Medium · CVSS 4.0
- Exploit chance (EPSS)
- 0.11%
- Chance of exploitation in the next 30 days. Higher than 1.44% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-346 Origin Validation Error
- Fix
16.3.8- Upgrade next to this version or later
Description
The Next.js development server (next dev) exposes a Model Context Protocol endpoint that does not verify which website a request originates from, allowing a malicious website visited by the developer to read sensitive development data — including the project's location on disk, source code snippets from error reports, the route inventory, and development logs. Only applications run with next dev are affected. Production deployments do not serve this endpoint.
Affected versions
npm
| Package | Vulnerable | Fixed in |
|---|---|---|
| next | >= 16.0.0, < 16.3.8 |
16.3.8 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
next npm → 16.3.8
- npm
npm install next@16.3.8- yarn
yarn add next@16.3.8- pnpm
pnpm add next@16.3.8
Severity breakdown
CVSS 4.0 0.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- Present
- Privileges required
- None
- User interaction
- Passive
- Confidentiality (vulnerable system)
- Low
- Integrity (vulnerable system)
- Low
- Availability (vulnerable system)
- None
- Confidentiality (subsequent systems)
- None
- Integrity (subsequent systems)
- None
- Availability (subsequent systems)
- None
CVSS 3.1 5.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Weakness
CWE-346: Origin Validation Error
The product does not properly verify that the source of data or communication is valid.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-673q-mjm6-r5xr Next.js: Unauthenticated Remote Code Execution in `use cache` functions returning typed arrays | Critical | Also affects next |
| GHSA-2464-fhr4-w9xw Next.js: Unauthenticated Remote Code Execution in Image Optimization API when SVG files are used | Critical | Also affects next |
| GHSA-p3m5-59mp-jv5r Next.js: Denial of Service in App Router using Server Actions | High | Also affects next |
| GHSA-3w37-wq28-93x7 Next.js: Pending `use cache` fill can leak Draft Mode content into regular responses and persisted pages | Medium | Also affects next |
| GHSA-4jqv-mc3x-m676 Next.js has cache poisoning of SSG and ISR pages in self-hosted applications | Medium | Also affects next |
| GHSA-f87g-xv8r-7p7x Next.js has information disclosure in App Router metadata image routes via dynamicParams bypass | Medium | Also affects next |
| GHSA-mcj8-r9mp-w47p Next.js has cache poisoning in SSG/ISR rendering that leads to cross-user content substitution and persistent denial of service | Medium | Also affects next |
| GHSA-cjq9-62q9-8jv4 Next.js has Server-Side Request Forgery in Image Optimization | Medium | Also affects next |
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