GHSA-gfc2-9qmw-w7vh
MEDIUMGHSA-gfc2-9qmw-w7vh is a medium-severity (CVSS 6.5) vulnerability in glances. O3 Security confirms whether GHSA-gfc2-9qmw-w7vh is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Glances: Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS
Blast Radius
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Description
Summary
The Glances web server exposes a REST API (/api/4/*) that is accessible without authentication and allows cross-origin requests from any origin due to a permissive CORS policy (Access-Control-Allow-Origin: *).
This allows a malicious website to read sensitive system information from a running Glances instance in the victim’s browser, leading to cross-origin data exfiltration.
While a previous advisory exists for XML-RPC CORS issues, this report demonstrates that the REST API (/api/4/*) is also affected and exposes significantly more sensitive data.
Details
When Glances is started in web mode (e.g., glances -w -B 0.0.0.0), it exposes a REST API endpoint at:
http://<host>:61208/api/4/all
The server responds with:
Access-Control-Allow-Origin: *
This allows any origin to perform cross-origin requests and read responses.
The /api/4/all endpoint returns extensive system information, including:
- Process list (
processlist) - System details (hostname, OS, CPU info)
- Memory and disk usage
- Network interfaces and IP address
- Running services and metrics Because no authentication is required by default, this data is accessible to any web page.
PoC
-
Start Glances: glances -w -B 0.0.0.0
-
Create a malicious HTML file:
<!DOCTYPE html>
<html>
<body>
<script>
fetch("http://<victim-ip>:61208/api/4/all")
.then(r => r.json())
.then(data => {
console.log("DATA:", data);
});
</script>
</body>
</html>
- Open the file in a browser while Glances is running.
- Observe that the browser successfully retrieves sensitive system information from the API. This works cross-origin (e.g., from file:// or attacker-controlled domains).
Impact
A remote attacker can host a malicious website that, when visited by a victim running Glances, can:
- Read sensitive system information
- Enumerate running processes
- Identify network configuration and IP addresses
- Fingerprint the host system
This requires no authentication and no user interaction beyond visiting a web page. This represents a cross-origin information disclosure vulnerability and can aid further attacks such as reconnaissance or targeted exploitation.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | glances | all versions | 4.5.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for glances. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update glances to 4.5.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-gfc2-9qmw-w7vh 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.
How O3 protects you
O3 pinpoints whether GHSA-gfc2-9qmw-w7vh is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-gfc2-9qmw-w7vh. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-gfc2-9qmw-w7vh in your dependencies?
O3 detects GHSA-gfc2-9qmw-w7vh across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.