Fix upload path-traversal RCE vector, patch all known-vulnerable deps

Path traversal (CWE-22/CWE-73): event-image, branding (logo/favicon),
and event-attachment uploads built the saved filename from the
client-supplied original filename with no sanitization, and multer's
diskStorage joins that straight into the destination path. A crafted
filename containing `../` sequences could write the uploaded file
anywhere the server process has write access — reachable by any
supervisor-level account, and briefly pre-auth via the branding
uploads during initial /setup. Filenames are now always server-
generated (random bytes + validated extension); the original name is
kept only as display metadata.

Dependencies: express-rate-limit was declared only at the repo root
despite being required directly by backend/src/index.js, so a plain
`cd backend && npm install` (per the deployment doc) would never
install it — moved it into backend/package.json. Bumped next off a
version affected by a critical unauthenticated RCE (React Flight
protocol) and switched it from an exact pin to a caret range so future
patches install automatically. Bumped multer/nodemailer/jsonwebtoken/
uuid to patched versions, with an override forcing the vulnerable
nested uuid inside exceljs and the vulnerable postcss bundled inside
next to the patched versions too. `npm audit` is now clean (0
vulnerabilities) across root, backend, and frontend.

Hardening: jwt.verify() now pins algorithms: ['HS256'] instead of
trusting the token header; /uploads now serves with a restrictive CSP
and X-Content-Type-Options: nosniff so an uploaded SVG containing
<script> can't execute if opened directly.

Verified: backend's Jest suite passes, the backend boots and serves
real requests on the bumped deps, and `next build` compiles/type-
checks cleanly on the bumped frontend deps.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CSWFWQsjTc9GyffPiXEDQT

This commit is contained in:

joshua

2026-08-28 11:33:05 +02:00

co-authored by

Claude Sonnet 5

parent 5a416916c9

commit 032d3c032e

11 changed files with 2197 additions and 3160 deletions

									
										package.json
									
		-3
	
												View File
												
				@@ -17,8 +17,5 @@

				  "description": "",

				  "devDependencies": {

				    "concurrently": "^9.2.1"

				  },

				  "dependencies": {

				    "express-rate-limit": "^8.3.1"

				  }

				}