CVE-2026-44579
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.75%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.75% probability · 53th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770, CWE-833
- Affected
- vercel/next.js
- Source
- security-advisories@github.com
References
- https://github.com/vercel/next.js/security/advisories/GHSA-mg66-mrh9-m8jxMitigation, Vendor Advisory
- https://access.redhat.com/errata/RHSA-2026:34608
- https://access.redhat.com/errata/RHSA-2026:37272
- https://access.redhat.com/errata/RHSA-2026:40974
- https://access.redhat.com/errata/RHSA-2026:54435
- https://access.redhat.com/security/cve/CVE-2026-44579
- https://bugzilla.redhat.com/show_bug.cgi?id=2477193
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44579.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.