High
glances — security advisory
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.
- Products
- glances
- Affected versions
- 2.10-2, 2.11.1-1, 2.11.1-2, 2.11.1-3, 2.11.1-3ubuntu0.1~esm1, 2.3-1build1, 2.3-1ubuntu0.1~esm1, 3.1.0-1, 3.1.1-1, 3.1.3-1, 3.1.3-1ubuntu0.1~esm1, 3.1.5-1, 3.2.3.1+dfsg-1, 3.2.4.2+dfsg-1, 3.4.0.3+dfsg-1, 4.3.0.8+dfsg-1, 4.3.1+dfsg-1, 4.3.3+dfsg-1, 4.5.4+dfsg-1, 4.5.5+dfsg-1, 4.5.6+dfsg-1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-34839
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 31 Oct 2026, 02:08 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-34839
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
glances
Fixed versions: Not specified
Complete source record
{
"id": "53ed4225c88b41119aef00e7349119030f964cde74d8ccab858a975d743fc3b5",
"url": "https://osv.dev/vulnerability/UBUNTU-CVE-2026-34839",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "UBUNTU-CVE-2026-34839",
"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.",
"evidence": "osv:UBUNTU-CVE-2026-34839",
"products": [
{
"name": {
"value": "glances",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.3-1build1",
"evidence": "/affected/0/versions"
},
{
"value": "2.3-1ubuntu0.1~esm1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "2.10-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.11.1-1",
"evidence": "/affected/1/versions"
},
{
"value": "2.11.1-2",
"evidence": "/affected/1/versions"
},
{
"value": "2.11.1-3",
"evidence": "/affected/1/versions"
},
{
"value": "2.11.1-3ubuntu0.1~esm1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.1.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.1.1-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.1.3-1",
"evidence": "/affected/2/versions"
},
{
"value": "3.1.3-1ubuntu0.1~esm1",
"evidence": "/affected/2/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/3/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.1.5-1",
"evidence": "/affected/3/versions"
},
{
"value": "3.2.3.1+dfsg-1",
"evidence": "/affected/3/versions"
},
{
"value": "3.2.4.2+dfsg-1",
"evidence": "/affected/3/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/4/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "3.4.0.3+dfsg-1",
"evidence": "/affected/4/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/5/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.3.0.8+dfsg-1",
"evidence": "/affected/5/versions"
},
{
"value": "4.3.1+dfsg-1",
"evidence": "/affected/5/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/6/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.3.3+dfsg-1",
"evidence": "/affected/6/versions"
},
{
"value": "4.5.4+dfsg-1",
"evidence": "/affected/6/versions"
},
{
"value": "4.5.5+dfsg-1",
"evidence": "/affected/6/versions"
},
{
"value": "4.5.6+dfsg-1",
"evidence": "/affected/6/versions"
}
]
},
{
"name": {
"value": "glances",
"evidence": "/affected/7/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.3.1+dfsg-1",
"evidence": "/affected/7/versions"
},
{
"value": "4.3.3+dfsg-1",
"evidence": "/affected/7/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "UBUNTU-CVE-2026-34839",
"aliases": [
"UBUNTU-CVE-2026-34839"
],
"metrics": [
{
"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"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=esm-apps%2Fxenial",
"ecosystem": "Ubuntu:Pro:16.04:LTS"
},
"versions": [
"2.3-1build1",
"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"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "2.3-1ubuntu0.1~esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=esm-apps%2Fbionic",
"ecosystem": "Ubuntu:Pro:18.04:LTS"
},
"versions": [
"2.10-2",
"2.11.1-1",
"2.11.1-2",
"2.11.1-3",
"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"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "2.11.1-3ubuntu0.1~esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=esm-apps%2Ffocal",
"ecosystem": "Ubuntu:Pro:20.04:LTS"
},
"versions": [
"3.1.0-1",
"3.1.1-1",
"3.1.3-1",
"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"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "3.1.3-1ubuntu0.1~esm1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=jammy",
"ecosystem": "Ubuntu:22.04:LTS"
},
"versions": [
"3.1.5-1",
"3.2.3.1+dfsg-1",
"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"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "3.2.4.2+dfsg-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=noble",
"ecosystem": "Ubuntu:24.04:LTS"
},
"versions": [
"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"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "3.4.0.3+dfsg-1"
}
]
}
},
{
"ranges": [
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],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=questing",
"ecosystem": "Ubuntu:25.10"
},
"versions": [
"4.3.0.8+dfsg-1",
"4.3.1+dfsg-1"
],
"database_specific": {
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},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
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}
]
}
},
{
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],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=stonking",
"ecosystem": "Ubuntu:26.10"
},
"versions": [
"4.3.3+dfsg-1",
"4.5.4+dfsg-1",
"4.5.5+dfsg-1",
"4.5.6+dfsg-1"
],
"database_specific": {
"source": "https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-34839.json"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "4.5.6+dfsg-1"
}
]
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "glances",
"purl": "pkg:deb/ubuntu/glances?arch=source&distro=resolute",
"ecosystem": "Ubuntu:26.04:LTS"
},
"versions": [
"4.3.1+dfsg-1",
"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"
},
"ecosystem_specific": {
"binaries": [
{
"binary_name": "glances",
"binary_version": "4.3.3+dfsg-1"
}
]
}
}
],
"modified": "2026-10-17T12:58:12.066494125Z",
"provider": "osv",
"upstream": [
"CVE-2026-34839"
],
"references": [
"https://ubuntu.com/security/CVE-2026-34839",
"https://www.cve.org/CVERecord?id=CVE-2026-34839"
]
},
"related_cves": [
{
"value": "CVE-2026-34839",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 358331,
"published_at": "2026-04-21T00:16:00+00:00"
}