CVE-2026-44572
Vercel Next.Js 12.2.0 – 15.5.16
Raw vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:LCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-44572 is a low-severity Acceptance of Extraneous Untrusted Data With Trusted Data (CWE-349) vulnerability in Vercel Next.Js. Its CVSS base score is 3.7 (Low).
Operationally, exploitation aligns with the MITRE ATT&CK technique Subvert Trust Controls (T1553); ranked at the 20th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to AC-4 (Information Flow Enforcement) and SI-10 (Information Input Validation) — see the control section below for these in your framework.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-30051
Vulnerability Data
Next.js is a React framework for building full-stack web applications. From 12.2.0 to before 15.5.16 and 16.2.5, an external client could send a x-nextjs-data header on a normal request to a path handled by middleware that returns a redirect. When…
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that happened, the middleware/proxy could treat the request as a data request and replace the standard Location redirect header with the internal x-nextjs-redirect header. Browsers do not follow x-nextjs-redirect, so the response became an unusable redirect for normal clients. If the application was deployed behind a CDN or reverse proxy that caches 3xx responses without varying on this header, a single attacker request could poison the cached redirect response for the affected path. Subsequent visitors could then receive a cached redirect response without a Location header, causing a denial of service for that redirect path until the cache entry expired or was purged. This vulnerability is fixed in 15.5.16 and 16.2.5.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 5 hardening rules · 2 OS baselines
V1.2.2V10.4.7V3.7.3V5.3.1
Mitigating Controls (NIST 800-53 r5) AI
Information flow enforcement can block untrusted data from being accepted or processed as if it were trusted.
Input validation directly stops acceptance of untrusted data mixed into trusted inputs.
Associating security attributes with data allows the system to distinguish and reject extraneous untrusted portions.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly address proper trust-boundary enforcement and input validation, preventing this class of weakness during development.
Cryptographic integrity checks on data-at-rest can detect tampering or substitution of untrusted content mixed with trusted data.
Cryptographic integrity mechanisms on data-in-transit can prevent acceptance of extraneous untrusted data by validating origin and detecting modification.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can detect the weakness but does not itself implement preventive controls.
Secure development lifecycle mandates input validation and trust-boundary enforcement that directly prevents acceptance of untrusted data alongside trusted data.
Application security requirements explicitly call for strict separation and validation of trusted versus untrusted data sources.
Secure architecture principles require explicit trust boundaries and data-origin checks that mitigate mixing of trusted and untrusted inputs.
Secure coding standards mandate input sanitization and provenance checks that prevent acceptance of extraneous untrusted data.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. prevents CWE-349