GHSA-gfc2-9qmw-w7vh

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Source
https://github.com/advisories/GHSA-gfc2-9qmw-w7vh
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-gfc2-9qmw-w7vh/GHSA-gfc2-9qmw-w7vh.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-gfc2-9qmw-w7vh
Aliases
  • CVE-2026-34839
Published
2026-04-21T15:14:40Z
Modified
2026-04-21T15:41:41.588501Z
Severity
  • 7.1 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Glances: Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS
Details

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

  1. Start Glances: glances -w -B 0.0.0.0

  2. 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>

2. Open the file in a browser while Glances is running. 3. 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.

Database specific 
{
    "severity": "HIGH",
    "github_reviewed": true,
    "nvd_published_at": "2026-04-21T00:16:27Z",
    "cwe_ids": [
        "CWE-200",
        "CWE-306",
        "CWE-942"
    ],
    "github_reviewed_at": "2026-04-21T15:14:40Z"
}
References

Affected packages

PyPI / glances

Package

Name
glances
View open source insights on deps.dev
Purl
pkg:pypi/glances

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
4.5.4

Affected versions

1.*
1.3.1
1.3.2
1.3.3
1.3.4
1.3.5
1.3.6
1.3.7
1.4
1.4.1
1.4.1.1
1.4.2
1.4.2.1
1.5
1.5.1
1.5.2
1.6
1.6.1
1.7
1.7.1
1.7.2
1.7.3
1.7.4
1.7.5
1.7.6
1.7.7
2.*
2.0
2.0.1
2.1
2.1.1
2.1.2
2.2
2.2.1
2.3
2.4
2.4.1
2.4.2
2.5
2.5.1
2.6
2.6.1
2.6.2
2.7
2.7.1
2.8
2.8.1
2.8.2
2.8.3
2.8.4
2.8.5
2.8.6
2.8.7
2.8.8
2.9.0
2.9.1
2.10
2.11
2.11.1
3.*
3.0
3.0.1
3.0.2
3.1.0
3.1.1
3.1.2
3.1.3
3.1.4
3.1.4.1
3.1.5
3.1.6
3.1.6.1
3.1.6.2
3.1.7
3.2.0
3.2.1
3.2.2
3.2.3
3.2.3.1
3.2.4
3.2.4.1
3.2.4.2
3.2.5
3.2.6.1
3.2.6.2
3.2.6.3
3.2.6.4
3.2.7
3.3.0
3.3.0.1
3.3.0.2
3.3.0.3
3.3.0.4
3.3.1
3.3.1.1
3.4.0
3.4.0.1
3.4.0.2
3.4.0.3
3.4.0.4
3.4.0.5
4.*
4.0.1
4.0.2
4.0.3
4.0.4
4.0.5
4.0.6
4.0.7
4.0.8
4.1.0
4.1.1
4.1.2
4.2.0
4.2.1
4.3.0
4.3.0.1
4.3.0.3
4.3.0.4
4.3.0.5
4.3.0.6
4.3.0.7
4.3.0.8
4.3.1
4.3.2
4.3.3
4.4.0
4.4.1
4.5.0
4.5.0.1
4.5.0.2
4.5.0.3
4.5.0.4
4.5.0.5
4.5.1
4.5.2
4.5.3

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/04/GHSA-gfc2-9qmw-w7vh/GHSA-gfc2-9qmw-w7vh.json"