Category

Middleware

Security vulnerabilities and automated fixes for middleware issues

11 posts found

critical5 min

How Broken Object-Level Authorization happens in Express.js and how to fix it

A critical authorization flaw in `src/v1/routes/index.js` allowed any authenticated API key holder to access arbitrary budgets by manipulating the `budgetSyncId` URL parameter. The fix introduces an environment-based allowlist that validates budget access before processing requests.

#authorization#express-js#bola+3 more
A
anupamme
Sep 7, 2026
high6 min

How Missing Rate Limiting Leads to Denial of Service in Express.js and How to Fix It

A high-severity denial of service vulnerability in `src/index.js` allowed attackers to exhaust server resources through unlimited requests to `/api/register` and `/api/captcha`. The fix implements in-memory rate limiting middleware, restricting captcha generation to 20 requests per minute and registration to 10 requests per minute per IP.

#security#express-js#rate-limiting+3 more
A
anupamme
Sep 7, 2026
high7 min

How CSRF vulnerabilities happen in Express.js and how to fix them

A HIGH severity Cross-Site Request Forgery (CSRF) vulnerability was found in `integrationExamples/topics/topics-server.js`, an Express.js demo server that lacked any CSRF protection middleware. The file was deleted entirely after assessment determined it posed unnecessary risk to downstream consumers of this Node.js library.

#security#express-js#csrf+3 more
A
anupamme
Aug 31, 2026
critical6 min

How Rate Limiting Vulnerabilities Happen in FastAPI and How to Fix Them

A critical denial-of-service vulnerability was discovered in a FastAPI application controlling Tesla Powerwall systems, where all 113+ API endpoints—including critical control endpoints for `/control/reserve` and `/control/mode`—lacked any rate limiting protection. An attacker could flood these endpoints with unlimited requests, exhausting server resources and disrupting powerwall monitoring and control operations. The fix introduces a configurable, pure-ASGI rate limiting middleware that can be

#security#fastapi#python+4 more
A
anupamme
Aug 31, 2026
high7 min

How Arbitrary File Read happens in Python LangSmith SDK and how to fix it

A high-severity arbitrary server-side file read vulnerability (GHSA-f4xh-w4cj-qxq8) was discovered in LangSmith SDK's `TracingMiddleware`, affecting versions prior to 0.8.18. An attacker able to influence tracing requests could potentially read arbitrary files from the server's filesystem. Upgrading from version 0.8.15 to 0.8.18 in `poetry.lock` and `pyproject.toml` closes the attack surface entirely.

#path-traversal#python#langsmith+3 more
A
anupamme
Aug 26, 2026
high8 min

How Middleware and Proxy Bypass happens in Next.js App Router and how to fix it

CVE-2026-64642 is a high-severity authentication bypass vulnerability in Next.js that affects App Router applications using Turbopack with a single locale configuration. The flaw allows attackers to circumvent middleware and proxy security controls, potentially gaining unauthorized access to protected routes. Upgrading from Next.js 16.2.7 to 16.2.11 closes the vulnerability entirely.

#authentication#nextjs#javascript+3 more
A
anupamme
Aug 26, 2026
high6 min

How javascript.express.security.audit.express-check-csurf-middleware-usage.express-check-csurf-middleware-usage happens in Express.js and how to fix it

An Express.js application in `src/server.js` was missing CSRF (Cross-Site Request Forgery) protection middleware, leaving all state-changing endpoints vulnerable to forged requests from malicious sites. The fix introduces the `csrf` package to generate and validate tokens on non-GET requests, while exempting API-key-authenticated clients. This defensive hardening raises the bar against automated exploit chaining.

#security#csrf#express-js+3 more
A
anupamme
Aug 24, 2026
high6 min

How javascript.express.security.audit.express-check-csurf-middleware-usage.express-check-csurf-middleware-usage happens in Express.js and how to fix it

A publicly accessible Express.js API endpoint in `app/api/cameras.js` was missing CSRF protection, leaving state-changing requests (POST, PUT, DELETE, PATCH) vulnerable to cross-site request forgery attacks. The fix introduces Origin/Referer header validation middleware in `app/index.js` and removes a redundant Express instance from `cameras.js` that bypassed the application's middleware chain.

#security#csrf#express-js+3 more
A
anupamme
Aug 23, 2026
high7 min

How Authentication Bypass happens in Next.js App Router with Turbopack and how to fix it

A critical authentication bypass vulnerability (CVE-2026-64642) was discovered in Next.js versions prior to 16.2.11, specifically affecting App Router applications using Turbopack with a single locale configuration. This vulnerability allowed attackers to bypass middleware and proxy protections, potentially gaining unauthorized access to protected routes and resources that should have been secured by authentication checks.

#nextjs#authentication-bypass#cve-2026-64642+4 more
A
anupamme
Aug 7, 2026
critical6 min

How missing authorization enforcement happens in Node.js Express routers and how to fix it

A critical authorization bypass was discovered in lib/router.js where readOnly and noDelete configuration options were only enforced through UI controls, not server-side middleware. Any authenticated user could bypass these restrictions by sending direct HTTP requests to perform destructive operations like database deletion or document modification. The fix adds Express middleware that enforces these security modes at the server level, blocking POST, PUT, and DELETE requests when appropriate.

#security#authorization#node.js+4 more
A
anupamme
Jul 31, 2026
high7 min

How Middleware/Proxy Bypass Happens in Next.js App Router with Turbopack and Single Locale and How to Fix It

A critical middleware and proxy bypass vulnerability (CVE-2026-64642) was discovered in Next.js 16.0.7 when using the App Router with Turbopack and single locale configurations. This vulnerability could allow attackers to circumvent security middleware and access protected routes. The fix requires upgrading Next.js from version 16.0.7 to 16.2.11, which patches the routing logic that handles locale-based request interception.

#next.js#security#middleware+4 more
A
anupamme
Jul 23, 2026