CVE-2026-111707

Description

99AI through 4.3.0 contains an insecure direct object reference vulnerability that allows unauthenticated attackers to read other users' chat messages because querySingleChat lacks an owner check. Attackers can send a fingerprint header to obtain a visitor JWT and iterate sequential chatId values to retrieve other users' message content and task data.

References

• https://github.com/vastxie/99AI
• https://github.com/vastxie/99AI/blob/v4.3.0/service/src/common/auth/jwtAuth.guard.ts
• https://github.com/vastxie/99AI/blob/v4.3.0/service/src/modules/chatLog/chatLog.service.ts#L463-L475
• https://hackmd.io/@hieuPenguinnn/99ai-chatlog-unauth-export-and-idor
• https://www.vulncheck.com/advisories/99ai-through-4.3.0-idor-via-api-chatlog-querysinglechat-chat-message-disclosure