CVE-2025-59472

CVE-2025-59472 is a medium-severity vulnerability in Vercel Next.js with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Description

A denial of service vulnerability exists in Next.js versions with Partial Prerendering (PPR) enabled when running in minimal mode. The PPR resume endpoint accepts unauthenticated POST requests with the `Next-Resume: 1` header and processes attacker-controlled postponed state data. Two closely related vulnerabilities allow an attacker to crash the server process through memory exhaustion: 1. **Unbounded request body buffering**: The server buffers the entire POST request body into memory using `Buffer.concat()` without enforcing any size limit, allowing arbitrarily large payloads to exhaust available memory. 2. **Unbounded decompression (zipbomb)**: The resume data cache is decompressed using `inflateSync()` without limiting the decompressed output size. A small compressed payload can expand to hundreds of megabytes or gigabytes, causing memory exhaustion. Both attack vectors result in a fatal V8 out-of-memory error (`FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory`) causing the Node.js process to terminate. The zipbomb variant is particularly dangerous as it can bypass reverse proxy request size limits while still causing large memory allocation on the server. To be affected you must have an application running with `experimental.ppr: true` or `cacheComponents: true` configured along with the NEXT_PRIVATE_MINIMAL_MODE=1 environment variable. Strongly consider upgrading to 15.6.0-canary.61 or 16.1.5 to reduce risk and prevent availability issues in Next applications.

Frequently asked questions

What is CVE-2025-59472?
A denial of service vulnerability exists in Next.js versions with Partial Prerendering (PPR) enabled when running in minimal mode. The PPR resume endpoint accepts unauthenticated POST requests with the `Next-Resume: 1` header and processes attacker-controlled postponed state data. Two closely related vulnerabilities allow an attacker to crash the server process through memory exhaustion: 1. **Unbounded request body buffering**: The server buffers the entire POST request body into memory using `Buffer.concat()` without enforcing any size limit, allowing arbitrarily large payloads to exhaust available memory. 2. **Unbounded decompression (zipbomb)**: The resume data cache is decompressed using `inflateSync()` without limiting the decompressed output size. A small compressed payload can expand to hundreds of megabytes or gigabytes, causing memory exhaustion. Both attack vectors result in a fatal V8 out-of-memory error (`FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory`) causing the Node.js process to terminate. The zipbomb variant is particularly dangerous as it can bypass reverse proxy request size limits while still causing large memory allocation on the server. To be affected you must have an application running with `experimental.ppr: true` or `cacheComponents: true` configured along with the NEXT_PRIVATE_MINIMAL_MODE=1 environment variable. Strongly consider upgrading to 15.6.0-canary.61 or 16.1.5 to reduce risk and prevent availability issues in Next applications.
How severe is CVE-2025-59472?
CVE-2025-59472 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-59472 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-59472?
CVE-2025-59472 primarily affects Vercel Next.js. In total, 63 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-59472?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-59472 have an EU (EUVD) identifier?
Yes. CVE-2025-59472 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-206333.
When was CVE-2025-59472 published?
CVE-2025-59472 was published on 2026-01-26 and last updated on 2026-06-17.

References

Affected products (63)

More vulnerabilities in Vercel Next.js

All CVEs affecting Vercel Next.js →

Other CWE-400 (Uncontrolled Resource Consumption) vulnerabilities

Browse all CWE-400 (Uncontrolled Resource Consumption) vulnerabilities →