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TI-2026-27083 Aliases CVE-2026-34839GHSA-gfc2-9qmw-w7vh

Glances Vulnerable to Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS

Priority HIGH 73CWE-200Published · Updated

Key facts

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

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-200 and CWE-306.

Summary

Glances is an open-source system cross-platform monitoring tool. Prior to version 4.5.4, 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. Version 4.5.4 patches the issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00408 35th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed glances (nicolargo): 4.5.4Glances (PyPI): 4.5.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

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

Affected products

VendorProductAffected versionsFixed inStatusSource
nicolargoglancesbefore 4.5.44.5.4Patch availableCNA
—Glances (PyPI)before 4.5.44.5.4Patch availableGHSA-gfc2-9qmw-w7vh
  • glances Vendornicolargo Affected before 4.5.4 Fixed in 4.5.4 Patch available CNA
  • Glances (PyPI) Vendor— Affected before 4.5.4 Fixed in 4.5.4 Patch available GHSA-gfc2-9qmw-w7vh

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:nicolargo:glances:*:*:*:*:*:*:*:*before 4.5.4Vulnerablenicolargo
  • cpe:2.3:a:nicolargo:glances:*:*:*:*:*:*:*:* Versions before 4.5.4 Vulnerable ·nicolargo

Remediation

  • Fix · CNA glances (nicolargo) Fixed in 4.5.4
  • Fix · GHSA-gfc2-9qmw-w7vh Glances (PyPI) Fixed in 4.5.4 Advisory →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-34839
  2. 2026-10-03 Alias added: GHSA-gfc2-9qmw-w7vh

References

Exploit 1

Patch 1

Advisory 1

Other 1

  • TI-2026-25142 Glances's Browser API Exposes Reusable Downstream Credentials via `/api/4/serverslist` CVSS 3.1CRITICAL 9.1
  • TI-2026-25106 Glances exposes the REST API without authentication CVSS 4.0HIGH 8.7
  • TI-2026-25120 Glances has a SQL Injection in DuckDB Export via Unparameterized DDL Statements CVSS 3.1CRITICAL 9.1
  • TI-2026-25118 Glances has Incomplete Secrets Redaction: /api/v4/args Endpoint Leaks Password Hash and SNMP Credentials CVSS 3.1HIGH 7.5
  • TI-2026-25143 Glances Central Browser Autodiscovery Leaks Reusable Credentials to Zeroconf-Spoofed Servers CVSS 3.1HIGH 8.1
  • TI-2026-25119 Glances's Default CORS Configuration Allows Cross-Origin Credential Theft CVSS 3.1HIGH 8.1
See all 14 →

Sources

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