CVE-2025-29927 | Authorization Bypass in Next.js Middleware

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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.

Published: 2025-03-21 Last update: 2025-09-10 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-29927 is rated High Exploit Risk (85.9/100): CVSS Critical severity, with high exploitation likelihood (EPSS 92.12%, 100th percentile). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2025-29927

EDB-ID Source Kind Published Link
52124 exploit_db edb 2025-04-05 Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2025-29927

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-24 92.55% 92.12% -0.43%
2 2026-05-23 92.31% 92.55% +0.24%
3 2026-05-22 — 92.31% —

Full EPSS history (74 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-29927

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 5.2 [email protected]

Weakness enumeration for CVE-2025-29927

GitHub Security Advisory for CVE-2025-29927

GHSA-f82v-jwr5-mffw · Severity: critical · Ecosystem: npm — Authorization Bypass in Next.js Middleware

OS Trackers for CVE-2025-29927

vendor priority summary link
redhat critical — https://access.redhat.com/security/cve/CVE-2025-29927

Affected software / configurations for CVE-2025-29927

Vendor Product Version Raw CPE
vercel next.js >= 11.1.4, < 12.3.5 cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*
vercel next.js >= 13.0.0, < 13.5.9 cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*
vercel next.js >= 14.0.0, < 14.2.25 cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*
vercel next.js >= 15.0.0, < 15.2.3 cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*

References for CVE-2025-29927

cvelogic Threat Intelligence