# CVE-2026-34839: glances: Glances is an open-source system cross-platform monitoring tool

CVE-2026-34839 is fixed in glances on 1 platform by DEBIAN-CVE-2026-34839 (version 4.5.4+dfsg-1), released May 15, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-34839
- Priority: Routine
- CVSS: 6.5 (medium)
- EPSS: 0.0041
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 21, 2026

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | glances Debian 14 | 4.5.4+dfsg-1 | [DEBIAN-CVE-2026-34839](https://patchblox.com/security/data/fix/linux/debian-cve-2026-34839.md) | May 15, 2026 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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