CVE-2026-34839

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/nicolargo/glances/commit/fdfb977b1d91b5e410bc06c4e19f8bedb0005ce9	Patch
https://github.com/nicolargo/glances/security/advisories/GHSA-gfc2-9qmw-w7vh	Exploit Vendor Advisory
https://github.com/nicolargo/glances/security/advisories/GHSA-gfc2-9qmw-w7vh	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nicolargo:glances:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-21 00:16

Updated : 2026-06-17 10:39

NVD link : CVE-2026-34839

Mitre link : CVE-2026-34839

CVE.ORG link : CVE-2026-34839

JSON object : View

Products Affected

nicolargo

glances

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

CWE-306

Missing Authentication for Critical Function

CWE-942

Permissive Cross-domain Security Policy with Untrusted Domains

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