{"id":"UBUNTU-CVE-2026-34839","details":"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.","modified":"2026-05-20T16:25:34.758822210Z","published":"2026-04-21T00:16:00Z","upstream":["CVE-2026-34839"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-34839"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-34839"}],"affected":[{"package":{"name":"glances","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/glances?arch=source&distro=esm-apps%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.3-1build1","2.3-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"2.3-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}},{"package":{"name":"glances","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/glances?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.10-2","2.11.1-1","2.11.1-2","2.11.1-3","2.11.1-3ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"2.11.1-3ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}},{"package":{"name":"glances","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/glances?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.0-1","3.1.1-1","3.1.3-1","3.1.3-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"3.1.3-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}},{"package":{"name":"glances","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/glances?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.5-1","3.2.3.1+dfsg-1","3.2.4.2+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"3.2.4.2+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}},{"package":{"name":"glances","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/glances?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.4.0.3+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"3.4.0.3+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}},{"package":{"name":"glances","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/glances?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.0.8+dfsg-1","4.3.1+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"4.3.1+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}},{"package":{"name":"glances","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/glances?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.3.1+dfsg-1","4.3.3+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"glances","binary_version":"4.3.3+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"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"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N"},{"type":"Ubuntu","score":"medium"}]}