99AI: Missing authentication in chat log export (CVE-2026-111706)
Summary
99AI through version 4.3.0 exposes the POST /api/chatLog/exportExcel route without authentication. An unauthenticated remote attacker can download Excel files containing all users' usernames, email addresses, prompts and AI answers. No login or user interaction is required, so the risk is high for instances reachable from the internet.
Affected
- vastxie 99AI up to and including 4.3.0
- Versions above 4.3.0 are listed as unaffected by the CNA data
Fixed in
Unknown. No vendor advisory or fixed version was found at the time of writing.
Workaround
- Block the route /api/chatLog/exportExcel at the reverse proxy, WAF or firewall, or allow access only from trusted networks
- Require authentication in front of the route until a fix is available
- Disable the chat log export feature if it is not needed
Exploitation
- Exploited in the wild: no evidence found; CISA KEV not checked directly
- A third-party write-up exists; its contents were not verified
- CISA SSVC: exploitation none, automatable yes, technical impact partial
- Attack complexity is low; the attacker needs only network access to the endpoint
Our recommendation
- Check whether any 99AI instance is running version 4.3.0 or earlier and reachable from the internet
- Restrict or authenticate the export route immediately
- Review web server logs for POST requests to /api/chatLog/exportExcel from unknown sources
- Check whether exported files have left the environment and assess data-protection obligations under the Swiss FADP with the legal contact
- Patch or restrict the related CVE-2026-111707 at the same time
- Monitor the vendor repository for a fixed release
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- VulnCheck advisory www.vulncheck.com
- Vendor repository 99AI github.com
- Controller code reference github.com
- Service code reference github.com
- Third-party write-up (HackMD) hackmd.io
- VulDB entry vuldb.com
- VulDB CVE page vuldb.com
- Strix CVE page www.strix.ai
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 02:12.
Original description (NVD)
99AI through 4.3.0 contains a missing authentication vulnerability in the POST /api/chatLog/exportExcel route that allows unauthenticated attackers to export all users' chat logs. Attackers can send requests with controlled page, size, and optional email fields to download xlsx files containing usernames, emails, prompts, and AI answers.
NVD references (5)
- https://github.com/vastxie/99AI
- https://github.com/vastxie/99AI/blob/v4.3.0/service/src/modules/chatLog/chatLog.controller.ts#L47-L52
- https://github.com/vastxie/99AI/blob/v4.3.0/service/src/modules/chatLog/chatLog.service.ts#L104-L155
- https://hackmd.io/@hieuPenguinnn/99ai-chatlog-unauth-export-and-idor
- https://www.vulncheck.com/advisories/99ai-through-4.3.0-unauthenticated-information-disclosure-via-chatlog-ex…
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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