GHSA-r2fc-ccr8-96c4 CVE-2025-49005
Next.js has a Cache poisoning vulnerability due to omission of the Vary header
- Severity
- 3.7 / 10
- Low · CVSS 3.1
- Exploit chance (EPSS)
- 0.49%
- Chance of exploitation in the next 30 days. Higher than 42.19% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
- Fix
15.3.3- Upgrade next to this version or later
Description
Summary
A cache poisoning issue in Next.js App Router >=15.3.0 and < 15.3.3 may have allowed RSC payloads to be cached and served in place of HTML, under specific conditions involving middleware and redirects. This issue has been fixed in Next.js 15.3.3.
Users on affected versions should upgrade immediately and redeploy to ensure proper caching behavior.
More details: CVE-2025-49005
Affected versions
npm
| Package | Vulnerable | Fixed in |
|---|---|---|
| next | >= 15.3.0, < 15.3.3 |
15.3.3 |
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 → 15.3.3
- npm
npm install next@15.3.3- yarn
yarn add next@15.3.3- pnpm
pnpm add next@15.3.3
Severity breakdown
CVSS 3.1 3.7
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
- Attack vector
- Network
- Attack complexity
- High
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Weakness
CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
How to prevent it
- Implementation: Use a web server that employs a strict HTTP parsing procedure, such as Apache [REF-433].
- Implementation: Use only SSL communication.
- Implementation: Terminate the client session after each request.
- System Configuration: Turn all pages to non-cacheable.
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-39w2-rjm5-chcv Next.js has information disclosure in development server's Model Context Protocol endpoint | 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 |
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