High 7.7Published Apr 20, 2026

CVE-2026-34839Glances Vulnerable to Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS

Updated under an hour ago (Oct 25, 2026, 11:00 PM ET)

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No exploitation reported and no EPSS estimate yet.

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Every CVE for nicolargo glances

Exploited in the last 30 days

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: 7.7 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
Weakness (CWE): CWE-200, CWE-942, CWE-306
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Apr 21, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

nicolargo glances nicolargo:glances (from the name)	before 4.5.4	CNA record
nicolargo glances nicolargo:glances	before 4.5.4	NVD

References

https://github.com/nicolargo/glances/security/advisories/GHSA-gfc2-9qmw-w7vhx-refsource-confirm, exploit, vendor-advisory
https://github.com/nicolargo/glances/commit/fdfb977b1d91b5e410bc06c4e19f8bedb0005ce9x-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.