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.
References6
- github.com/vastxie/99AI
- github.com/vastxie/99AI/blob/v4.3.0/service/src/common/auth/jwt…
- github.com/vastxie/99AI/blob/v4.3.0/service/src/modules/chatLog…
- hackmd.io/@hieuPenguinnn/99ai-chatlog-unauth-export-and-idor
- www.vulncheck.com/advisories/99ai-through-4.3.0-idor-via-api-ch…
- hackmd.io/@hieuPenguinnn/99ai-chatlog-unauth-export-and-idor
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 4.0
-
6.9
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 24 · as of 10 November 2026
- CWE
- CWE-639
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.