nagios4 — security advisory
Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 are vulnerable to authenticated remote code execution via custom-variable macro injection through the Nagios Remote Data Processor (NRDP). When a custom variable defined on a host, service, or contact is referenced in a shell-executed command line, an authenticated attacker with NRDP access can inject OS commands through the macro value. Exploitation requires a non-default configuration in which a custom variable is defined and referenced in a shell-executed command.
- Products
- nagios4
- Affected versions
- 4.4.6-4, 4.4.6-4+deb12u1, 4.4.6-4.1, 4.4.6-4.1+deb13u1, 4.5.12+ds-1
- Fixed versions
- 4.4.6-4+deb12u2, 4.4.6-4.1+deb13u2, 4.5.14+ds-1
- CVEs
- CVE-2026-48553
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 30 Oct 2026, 11:45 UTC · Revision 1
Source evidence
Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 are vulnerable to authenticated remote code execution via custom-variable macro injection through the Nagios Remote Data Processor (NRDP). When a custom variable defined on a host, service, or contact is referenced in a shell-executed command line, an authenticated attacker with NRDP access can inject OS commands through the macro value. Exploitation requires a non-default configuration in which a custom variable is defined and referenced in a shell-executed command.
osv:DEBIAN-CVE-2026-48553
nagios4
Fixed versions: 4.4.6-4+deb12u2
nagios4
Fixed versions: 4.4.6-4.1+deb13u2
nagios4
Fixed versions: 4.5.14+ds-1
Complete source record
{
"id": "f0dbd0ab881d0f9aeae5acd6525701b9dff1d1954723aa36355ebea0ac903826",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-48553",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-48553",
"summary": "Nagios Core before 4.5.13 and Nagios XI before 2026R1.5 are vulnerable to authenticated remote code execution via custom-variable macro injection through the Nagios Remote Data Processor (NRDP). When a custom variable defined on a host, service, or contact is referenced in a shell-executed command line, an authenticated attacker with NRDP access can inject OS commands through the macro value. Exploitation requires a non-default configuration in which a custom variable is defined and referenced in a shell-executed command.",
"evidence": "osv:DEBIAN-CVE-2026-48553",
"products": [
{
"name": {
"value": "nagios4",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.4.6-4+deb12u2",
"evidence": "/affected/0/ranges"
}
],
"affected_versions": [
{
"value": "4.4.6-4",
"evidence": "/affected/0/versions"
},
{
"value": "4.4.6-4+deb12u1",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "nagios4",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.4.6-4.1+deb13u2",
"evidence": "/affected/1/ranges"
}
],
"affected_versions": [
{
"value": "4.4.6-4.1",
"evidence": "/affected/1/versions"
},
{
"value": "4.4.6-4.1+deb13u1",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "nagios4",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.5.14+ds-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "4.4.6-4.1",
"evidence": "/affected/2/versions"
},
{
"value": "4.5.12+ds-1",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-48553",
"aliases": [
"DEBIAN-CVE-2026-48553"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.4.6-4+deb12u2"
}
]
}
],
"package": {
"name": "nagios4",
"purl": "pkg:deb/debian/nagios4?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"versions": [
"4.4.6-4",
"4.4.6-4+deb12u1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48553.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.4.6-4.1+deb13u2"
}
]
}
],
"package": {
"name": "nagios4",
"purl": "pkg:deb/debian/nagios4?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"4.4.6-4.1",
"4.4.6-4.1+deb13u1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48553.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.5.14+ds-1"
}
]
}
],
"package": {
"name": "nagios4",
"purl": "pkg:deb/debian/nagios4?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"4.4.6-4.1",
"4.5.12+ds-1"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-48553.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-14T06:00:20.233540626Z",
"provider": "osv",
"upstream": [
"CVE-2026-48553"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-48553"
]
},
"related_cves": [
{
"value": "CVE-2026-48553",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 315275,
"published_at": "2026-08-12T17:17:27.697+00:00"
}