CVE-2026-44649
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk12th percentile - higher than 12% of all known CVEs
Summary
SillyTavern, a locally installed user interface, accepts Remote-User and X-Authentik-Username HTTP headers for automatic login when SSO is configured, without validating they originate from a trusted proxy.
Risk Assessment
Any network client with access to the SillyTavern port can impersonate any user, including administrators, without a password, leading to full compromise.
Recommendation
Update SillyTavern to version 1.18.0 or later, which contains the fix.
Original NVD description (English source)
SillyTavern is a locally installed user interface that allows users to interact with text generation large language models, image generation engines, and text-to-speech voice models. Prior to 1.18.0, SillyTavern accepts Remote-User (Authelia) and X-Authentik-Username (Authentik) HTTP headers to automatically log in users when SSO is configured. There is no validation that these headers originate from a trusted reverse proxy. Any network client that can reach the SillyTavern port directly can inject these headers and authenticate as any user, including administrators, without a password. This vulnerability is exploitable only when sso.autheliaAuth: true or sso.authentikAuth: true is set in config.yaml (both default to false). This vulnerability is fixed in 1.18.0.