CVE-2026-34839 (GCVE-0-2026-34839)

Vulnerability from cvelistv5 – Published: 2026-04-20 23:09 – Updated: 2026-04-21 19:37
VLAI?
Title
Glances Vulnerable to Cross-Origin Information Disclosure via Unauthenticated REST API (/api/4) due to Permissive CORS
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.
Severity ?
7.7 (High)
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
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
  • CWE-942 - Permissive Cross-domain Policy with Untrusted Domains
  • CWE-306 - Missing Authentication for Critical Function
Assigner
References
Impacted products
Vendor Product Version
nicolargo glances Affected: < 4.5.4
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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