CVE-2026-85695

CVE-2026-85695

FastChat contains an authentication bypass vulnerability in the /register_worker endpoint that allows unauthenticated attackers to register arbitrary worker addresses and perform server-side request forgery. Attackers can register malicious workers under victim model names to intercept user prompts, images, and responses, or probe internal network ports across the worker mesh.

Vulnerability class: Broken Authentication

CVSS v3 metric

CVSS v3 base score 9.4 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L.

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-85695?
CVE-2026-85695 is a critical-severity vulnerability, classified under Missing Authentication for Critical Function. CVSS score: 9.4/10. Published 2026-09-04.
How severe is CVE-2026-85695?
Critical severity. CVSS v3 base score is 9.4 out of 10.