TI-2026-32549 Aliases CVE-2026-44649 GHSA-gxx6-h3g6-vwjh

SillyTavern: Authentication Bypass via SSO Header Injection

HIGH 82CWE-290Published 2026-05-29 · Updated 2026-06-02

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Security bypass
Confidentiality · integrity · availability: High · High · High
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-290.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.00218 12th percentileScored 2026-11-07

Fix Fixed SillyTavern (SillyTavern): 1.18.0sillytavern (npm): 1.18.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
SillyTavern	SillyTavern	before 1.18.0	1.18.0	Patch available	CNA
—	sillytavern (npm)	before 1.18.0	1.18.0	Patch available	GHSA-gxx6-h3g6-vwjh

SillyTavern VendorSillyTavern Affected before 1.18.0 Fixed in 1.18.0 Patch available CNA
sillytavern (npm) Vendor— Affected before 1.18.0 Fixed in 1.18.0 Patch available GHSA-gxx6-h3g6-vwjh

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:sillytavern:sillytavern::::::::	—	—	SillyTavern

cpe:2.3:a:sillytavern:sillytavern:*:*:*:*:*:*:*:* Versions — — ·SillyTavern

Remediation

Fix · CNA SillyTavern (SillyTavern) Fixed in 1.18.0
Fix · GHSA-gxx6-h3g6-vwjh sillytavern (npm) Fixed in 1.18.0 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-44649
2026-10-03 Alias added: GHSA-gxx6-h3g6-vwjh

References

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-44649

Other 3

TI-2026-32550 SillyTavern: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CVSS 3.1CRITICAL 9.1
TI-2025-36763 SillyTavern Web Interface Vulnerable to DNS Rebinding CVSS 3.1CRITICAL 9.7
TI-2026-26773 Path traversal in SillyTavern CVSS 3.1HIGH 8.8
TI-2026-34089 SillyTavern: SSRF in SearXNG Search Proxy via Unvalidated baseUrl CVSS 3.1HIGH 8.5
TI-2026-70544 Pre-authentication denial of service in SillyTavern via body parsing CVSS 4.0HIGH 8.2
TI-2026-32548 SillyTavern: Existing sessions are not invalidated after password change, allowing session reuse and account takeover CVSS 3.1HIGH 7.5

See all 12 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences