CVE-2026-44576: CWE-436: Interpretation Conflict in vercel next.js
Next.js is a React framework for building full-stack web applications. From 14.2.0 to before 15.5.16 and 16.2.5, applications using React Server Components can be vulnerable to cache poisoning when shared caches do not correctly partition response variants. Under affected conditions, an attacker can cause an RSC response to be served from the original URL and poison shared cache entries so later visitors receive component payloads instead of the expected HTML. This vulnerability is fixed in 15.5.16 and 16.2.5.
AI Analysis
Technical Summary
CVE-2026-44576 affects the Next.js React framework in versions >=14.2.0 and <15.5.16, and >=16.0.0 and <16.2.5. The vulnerability arises from cache poisoning in React Server Components when shared caches do not correctly separate response variants. An attacker can cause a React Server Component (RSC) response to be served from the original URL and poison shared cache entries, leading to later visitors receiving component payloads instead of the expected HTML. This can impact the integrity and availability of the served content. The vulnerability is addressed in Next.js versions 15.5.16 and 16.2.5.
Potential Impact
The vulnerability allows an attacker to poison shared caches, causing users to receive incorrect component payloads instead of the intended HTML. This can lead to integrity issues and potential denial of service due to improper content rendering. There is no indication of confidentiality impact. The CVSS score of 5.4 reflects a medium severity with network attack vector, high attack complexity, no privileges or user interaction required, and a scope change.
Mitigation Recommendations
A fix is available in Next.js versions 15.5.16 and 16.2.5. Users should upgrade to one of these versions or later to remediate this vulnerability. Since this is not a cloud service, remediation requires updating the affected software versions. Patch status is confirmed by the version information in the description.
CVE-2026-44576: CWE-436: Interpretation Conflict in vercel next.js
Description
Next.js is a React framework for building full-stack web applications. From 14.2.0 to before 15.5.16 and 16.2.5, applications using React Server Components can be vulnerable to cache poisoning when shared caches do not correctly partition response variants. Under affected conditions, an attacker can cause an RSC response to be served from the original URL and poison shared cache entries so later visitors receive component payloads instead of the expected HTML. This vulnerability is fixed in 15.5.16 and 16.2.5.
CVSS v3.1
Score 5.4medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-44576 affects the Next.js React framework in versions >=14.2.0 and <15.5.16, and >=16.0.0 and <16.2.5. The vulnerability arises from cache poisoning in React Server Components when shared caches do not correctly separate response variants. An attacker can cause a React Server Component (RSC) response to be served from the original URL and poison shared cache entries, leading to later visitors receiving component payloads instead of the expected HTML. This can impact the integrity and availability of the served content. The vulnerability is addressed in Next.js versions 15.5.16 and 16.2.5.
Potential Impact
The vulnerability allows an attacker to poison shared caches, causing users to receive incorrect component payloads instead of the intended HTML. This can lead to integrity issues and potential denial of service due to improper content rendering. There is no indication of confidentiality impact. The CVSS score of 5.4 reflects a medium severity with network attack vector, high attack complexity, no privileges or user interaction required, and a scope change.
Mitigation Recommendations
A fix is available in Next.js versions 15.5.16 and 16.2.5. Users should upgrade to one of these versions or later to remediate this vulnerability. Since this is not a cloud service, remediation requires updating the affected software versions. Patch status is confirmed by the version information in the description.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-06T21:49:12.424Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a04af94cbff5d8610ed299c
Added to database: 05/13/2026, 17:06:28 UTC
Last enriched: 05/20/2026, 18:26:37 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 111
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