CVE-2025-69211

Nest has a Fastify URL Encoding Middleware Bypass (TOCTOU)

HIGH
7.4
CVSS Score
Published: December 29, 2025 at 04:01 PM UTC
Updated: October 7, 2026 at 12:10 PM UTC
1 product affected across 1 vendorNest

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Severity
HIGH7.4
Exploit prediction
EPSS 0.4%
SSVC
PoC

Description

Nest is a framework for building scalable Node.js server-side applications. Versions prior to 11.1.11 have a Fastify URL encoding middleware bypass. A NestJS application is vulnerable if it uses `@nestjs/platform-fastify`; relies on `NestMiddleware` (via `MiddlewareConsumer`) for security checks (authentication, authorization, etc.), or through `app.use()`; and applies middleware to specific routes using string paths or controllers (e.g., `.forRoutes('admin')`). Exploitation can result in unauthenticated users accessing protected routes, restricted administrative endpoints becoming accessible to lower-privileged users, and/or middleware performing sanitization or validation being skipped. This issue is patched in `@nestjs/[email protected]`.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 11.1.11
Affected range stops below 11.1.11, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

SSVC — Action Prioritization

SSVCPoCNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-367

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