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CVE-2026-73973

Full vulnerability record from the local CVENow database.

Description

Linuxfabrik Monitoring Plugins provides monitoring plugins for Icinga, Nagios, and related systems. Prior to version 7.0.0, check-plugins/logfile/logfile accepted a free-form --filename path and opened it as root when invoked through the shipped nagios or icinga sudoers allowlist, without confining the resolved path to /var/log. An attacker who controls the monitoring account can select a root-readable file such as /etc/shadow and use --warning-regex . while leaving SUPPRESS_OUTPUT false, causing each nonempty line to be collected in warn_matches and returned through lib.base.oao(). The vulnerable flow passes the expanded scan_path directly to open(), and neither real-path containment nor an allowlist protects the sink. The same fix also confines mysql-logfile and openvpn-client-list paths, allows only documented log roots, and resolves symlinks and parent-directory traversal before checking containment. This issue is fixed in version 7.0.0.

Severity
MEDIUM
CVSS score
5.5 (v3.1)
Vulnerability status
Deferred
Source identifier
Published
2026-08-18 22:17:33.667000
Last modified
2026-10-22 16:09:59.560000
View original CVE JSON
{
  "id": "CVE-2026-73973",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-18T22:17:33.667",
  "lastModified": "2026-10-22T16:09:59.560",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Linuxfabrik Monitoring Plugins provides monitoring plugins for Icinga, Nagios, and related systems. Prior to version 7.0.0, check-plugins/logfile/logfile accepted a free-form --filename path and opened it as root when invoked through the shipped nagios or icinga sudoers allowlist, without confining the resolved path to /var/log. An attacker who controls the monitoring account can select a root-readable file such as /etc/shadow and use --warning-regex . while leaving SUPPRESS_OUTPUT false, causing each nonempty line to be collected in warn_matches and returned through lib.base.oao(). The vulnerable flow passes the expanded scan_path directly to open(), and neither real-path containment nor an allowlist protects the sink. The same fix also confines mysql-logfile and openvpn-client-list paths, allows only documented log roots, and resolves symlinks and parent-directory traversal before checking containment. This issue is fixed in version 7.0.0."
    },
    {
      "lang": "es",
      "value": "Linuxfabrik Monitoring Plugins proporciona plugins de monitorización para Icinga, Nagios y sistemas relacionados. Antes de la versión 7.0.0, check-plugins/logfile/logfile aceptaba una ruta --filename de formato libre y la abría como root cuando se invocaba a través de la lista de permitidos (allowlist) de sudoers de nagios o icinga incluida, sin confinar la ruta resuelta a /var/log. Un atacante que controla la cuenta de monitorización puede seleccionar un archivo legible por root como /etc/sha4dow y usar --warning-regex . mientras deja SUPPRESS_OUTPUT en false, haciendo que cada línea no vacía se recoja en warn_matches y se devuelva a través de lib.base.oao(). El flujo vulnerable pasa la scan_path expandida directamente a open(), y ni la contención de ruta real ni una lista de permitidos (allowlist) protegen el sumidero. La misma corrección también confina las rutas de MySQL-logfile y openvpn-client-list, permite solo raíces de registro documentadas y resuelve enlaces simbólicos y salto de directorio padre antes de verificar la contención. Este problema está corregido en la versión 7.0.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Linuxfabrik",
          "product": "monitoring-plugins",
          "versions": [
            {
              "version": "< 7.0.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "LOCAL",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-19T19:19:51.315696Z",
          "id": "CVE-2026-73973",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-22"
        },
        {
          "lang": "en",
          "value": "CWE-269"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/Linuxfabrik/monitoring-plugins/blob/ae486fc629e1ca9373e1b6dd5e395603ee453bbc/CHANGELOG.md#v700---2026-08-14",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Linuxfabrik/monitoring-plugins/commit/a0ca1268d84e0caf10442b9c7477d699b52d1c92",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Linuxfabrik/monitoring-plugins/releases/tag/v7.0.0",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-f54c-p5vg-mr5c",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/Linuxfabrik/monitoring-plugins/security/advisories/GHSA-f54c-p5vg-mr5c",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}