{"id":"CVE-2026-85695","title":"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","summary":"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 malici…","severity":"critical","cvss":9.4,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L","cwe":["CWE-306"],"published":"2026-09-04","updated":"2026-09-10","sourceUpdated":"2026-09-10T15:53:23.707","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-85695","references":[{"url":"https://github.com/lm-sys/FastChat","label":"disclosure@vulncheck.com"},{"url":"https://github.com/lm-sys/FastChat/blob/v0.2.36/fastchat/serve/controller.py","label":"disclosure@vulncheck.com"},{"url":"https://github.com/lm-sys/FastChat/issues/3886","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/fastchat-unauthenticated-worker-registration-ssrf-and-model-spoofing","label":"disclosure@vulncheck.com"}],"tags":["nvd"],"epss":0.00412,"epssPercentile":0.35229,"ingestedAt":"2026-09-10T16:57:28.706Z","slug":"CVE-2026-85695","body":"## Overview\n\nFastChat 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":52,"depthScoreParts":{"impact":51.7,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}