What is CVE-2025-29927?
Next.js is a React framework for building full-stack web applications. Starting in version 1.11.4 and prior to versions 12.3.5, 13.5.9, 14.2.25, and 15.2.3, it is possible to bypass authorization checks within a Next.js application, if the authorization check occurs in middleware. If patching to a safe version is infeasible, it is recommend that you prevent external user requests which contain the x-middleware-subrequest header from reaching your Next.js application. This vulnerability is fixed in 12.3.5, 13.5.9, 14.2.25, and 15.2.3.
The record classifies CVE-2025-29927 under weakness class CWE-285. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 587 days ago.
Severity and exploitation probability
- CVSS v3.1 base score
- 9.1 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - EPSS (FIRST)
- 99.2% probability of exploitation in the next 30 days, higher than 99.9% of all scored CVEs
- CISA KEV
- Not listed in the CISA Known Exploited Vulnerabilities catalog
- Threadlinqs priority
- 10/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- Published
- 2025-03-21, last modified 2025-04-08
Is CVE-2025-29927 being exploited?
Weaponised exploit code for CVE-2025-29927 is publicly available. 11 public proof-of-concept repositories are tracked for this identifier. A ProjectDiscovery Nuclei detection template exists (http/cves/2025/CVE-2025-29927.yaml). It currently carries a trending score of 40 in the Threadlinqs vulnerability feed.
- aydinnyunus/CVE-2025-29927 (github)
- AnonKryptiQuz/NextSploit (github)
- websecnl/CVE-2025-29927-PoC-Exploit (github)
- 6mile/nextjs-CVE-2025-29927 (github)
- azu/nextjs-cve-2025-29927-poc (github)
- lirantal/vulnerable-nextjs-14-CVE-2025-29927 (github)
- UNICORDev/exploit-CVE-2025-29927 (github)
- MuhammadWaseem29/CVE-2025-29927-POC (github)
Affected products and versions
- vercel: next.js
How to fix CVE-2025-29927
No vendor patch reference has been recorded for CVE-2025-29927 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.
Threat activity tracking CVE-2025-29927
2 tracked threats in the Threadlinqs corpus reference CVE-2025-29927, either in the campaign’s CVE list or as an indicator on the campaign record.
- PCPJack Worm — Cloud Credential Theft Framework Evicting TeamPCP Infections (CVE-2025-29927, CVE-2025-55182, CVE-2026-1357, CVE-2025-9501, CVE-2025-48703) — CRITICAL · 2026-05-07
- TeamPCP LiteLLM Supply Chain Attack — Trojaned PyPI Packages (v1.82.7/1.82.8) with Multi-Stage C2 Payload — CRITICAL · 2026-03-31
Sources
Enriched from CVE.org, FIRST EPSS, public proof-of-concept repositories, ProjectDiscovery Nuclei. Last verified by Threadlinqs on .