CVE-2026-64641: CWE-834: Excessive Iteration in vercel next.js
Next.js is a React framework for building full-stack web applications. In versions 13.0.0 through 15.5.20 and 16.0.0 through 16.2.10, crafted requests targeting Next.js applications using App Router with at least one Server Action can lead to excessive CPU usage blocking processing of further requests in the same process. This issue has been fixed in versions 15.5.21 and 16.2.11.
AI Analysis
Technical Summary
CVE-2026-64641 is a high-severity vulnerability in the Next.js React framework affecting versions 13.0.0 to 15.5.20 and 16.0.0 to 16.2.10. It involves excessive iteration triggered by crafted requests targeting applications using the App Router with Server Actions, resulting in high CPU consumption that blocks further request processing in the affected process. This denial-of-service-like condition is addressed by patches in versions 15.5.21 and 16.2.11.
Potential Impact
Exploitation of this vulnerability can lead to denial of service by causing excessive CPU usage, which blocks the processing of additional requests in the same server process. This can degrade application availability and responsiveness.
Mitigation Recommendations
Upgrade Next.js to version 15.5.21 or later if using the 13.x to 15.x series, or to version 16.2.11 or later if using the 16.x series. These versions contain fixes that address the excessive iteration vulnerability. No other mitigations are specified.
CVE-2026-64641: CWE-834: Excessive Iteration in vercel next.js
Description
Next.js is a React framework for building full-stack web applications. In versions 13.0.0 through 15.5.20 and 16.0.0 through 16.2.10, crafted requests targeting Next.js applications using App Router with at least one Server Action can lead to excessive CPU usage blocking processing of further requests in the same process. This issue has been fixed in versions 15.5.21 and 16.2.11.
CVSS v4.0
Score 8.2high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-64641 is a high-severity vulnerability in the Next.js React framework affecting versions 13.0.0 to 15.5.20 and 16.0.0 to 16.2.10. It involves excessive iteration triggered by crafted requests targeting applications using the App Router with Server Actions, resulting in high CPU consumption that blocks further request processing in the affected process. This denial-of-service-like condition is addressed by patches in versions 15.5.21 and 16.2.11.
Potential Impact
Exploitation of this vulnerability can lead to denial of service by causing excessive CPU usage, which blocks the processing of additional requests in the same server process. This can degrade application availability and responsiveness.
Mitigation Recommendations
Upgrade Next.js to version 15.5.21 or later if using the 13.x to 15.x series, or to version 16.2.11 or later if using the 16.x series. These versions contain fixes that address the excessive iteration vulnerability. No other mitigations are specified.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-m99w-x7hq-7vfj
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-64641"]
- Ecosystems
- ["npm"]
- Database Specific Severity
- HIGH
- Cvss Version
- 4.0
Threat ID: 6a616bcf9c2644c7f80dbeac
Added to database: 07/23/2026, 01:18:07 UTC
Last enriched: 07/30/2026, 15:29:13 UTC
Last updated: 09/03/2026, 22:52:13 UTC
Views: 187
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