CVE-2026-44579

CVE-2026-44579 is a high-severity vulnerability in Vercel Next.js with a CVSS 3.x base score of 7.5. 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-770.

Key facts

Description

Next.js is a React framework for building full-stack web applications. From to before 15.5.16 and 16.2.5, applications using Partial Prerendering through the Cache Components feature can be vulnerable to connection exhaustion through crafted POST requests to a server action. In affected configurations, a malicious request can trigger a request-body handling deadlock that leaves connections open for an extended period, consuming file descriptors and server capacity until legitimate users are denied service. This vulnerability is fixed in 15.5.16 and 16.2.5.

Frequently asked questions

What is CVE-2026-44579?
Next.js is a React framework for building full-stack web applications. From to before 15.5.16 and 16.2.5, applications using Partial Prerendering through the Cache Components feature can be vulnerable to connection exhaustion through crafted POST requests to a server action. In affected configurations, a malicious request can trigger a request-body handling deadlock that leaves connections open for an extended period, consuming file descriptors and server capacity until legitimate users are denied service. This vulnerability is fixed in 15.5.16 and 16.2.5.
How severe is CVE-2026-44579?
CVE-2026-44579 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-44579 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-44579?
CVE-2026-44579 affects Vercel Next.js. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-44579?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-44579 have an EU (EUVD) identifier?
Yes. CVE-2026-44579 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30081.
When was CVE-2026-44579 published?
CVE-2026-44579 was published on 2026-05-13 and last updated on 2026-07-03.

References

Affected products (1)

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