CVE-2026-91921

medium

Description

Cross-Site Scripting (XSS) vulnerability due to inadequate input sanitisation in the client-side rendering engine of the 1millionbot AI Chat Platform. An unauthenticated remote user could cause external hyperlinks to be rendered in the web interface by sending messages containing Markdown syntax and certain unsanitised content blocks. The impact is limited to the user’s own interactive session; no compromise of internal infrastructure, access to third-party data or impact on administrative panels has been identified.

References

https://www.incibe.es/en/incibe-cert/notices/aviso/cross-site-scripting-xss-1millionbots-ai-chatbot-platform

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-83880

Details

Source: Mitre, NVD

Published: 2026-09-21

Updated: 2026-09-22

Risk Information

CVSS v2

Base Score: 4.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.1

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Severity: Medium

CVSS v4

Base Score: 5.1

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

Severity: Medium

EPSS

EPSS: 0.00596