Vulnerability-Lookup

GHSA-R6WG-9VJ9-RM67

Vulnerability from github – Published: 2026-08-12 18:31 – Updated: 2026-08-12 18:31

Details

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.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

7.7 (High)


                  
                    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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-48553"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-78"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-12T17:17:27Z",
    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-r6wg-9vj9-rm67",
  "modified": "2026-08-12T18:31:20Z",
  "published": "2026-08-12T18:31:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-48553"
    },
    {
      "type": "WEB",
      "url": "https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog"
    },
    {
      "type": "WEB",
      "url": "https://www.nagios.com/security-disclosures/nagios-core"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/nagios-core-xi-authenticated-rce-via-custom-variable-macro-injection"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-48553 (GCVE-0-2026-48553)

Vulnerability from cvelistv5 – Published: 2026-08-12 16:46 – Updated: 2026-08-14 16:50

Title

Nagios Core / XI Authenticated RCE via Custom-Variable Macro Injection

Summary

Severity

7.7 (High)


                        
                          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

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-12 17:55 UTC

CWE

CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Assigner

VulnCheck

References

3 references

URL	Tags
https://www.nagios.com/security-disclosures/nagio…	vendor-advisorypatch
https://github.com/NagiosEnterprises/nagioscore/b…	release-notes
https://www.vulncheck.com/advisories/nagios-core-…	third-party-advisory

Impacted products

2 products

Vendor	Product	Version
Nagios Enterprises, LLC.	Nagios Core	Affected: 0 , < 4.5.13 (semver)
Nagios Enterprises, LLC.	Nagios XI	Affected: 0 , < 2026R1.5 (custom)

Date Public

2026-08-05 00:00

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-48553",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-12T17:55:13.472460Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-12T19:19:20.109Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "product": "Nagios Core",
          "vendor": "Nagios Enterprises, LLC.",
          "versions": [
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              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
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        },
        {
          "defaultStatus": "affected",
          "product": "Nagios XI",
          "vendor": "Nagios Enterprises, LLC.",
          "versions": [
            {
              "lessThan": "2026R1.5",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
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                  "criteria": "cpe:2.3:a:nagios:nagios_core:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "4.5.13",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:nagios:nagios_xi:*:*:*:*:*:*:*:*",
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              ],
              "negate": false,
              "operator": "OR"
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      "descriptions": [
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            "Recovery": "NOT_DEFINED",
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            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 7.7,
            "baseSeverity": "HIGH",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
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            "vulnIntegrityImpact": "HIGH",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
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          "scenarios": [
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            "version": "3.1"
          },
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          "scenarios": [
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      "problemTypes": [
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          "descriptions": [
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        },
        {
          "name": "Changelog",
          "tags": [
            "release-notes"
          ],
          "url": "https://github.com/NagiosEnterprises/nagioscore/blob/master/Changelog"
        },
        {
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            "third-party-advisory"
          ],
          "url": "https://www.vulncheck.com/advisories/nagios-core-xi-authenticated-rce-via-custom-variable-macro-injection"
        }
      ],
      "source": {
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    "cveId": "CVE-2026-48553",
    "datePublished": "2026-08-12T16:46:35.837Z",
    "dateReserved": "2026-05-21T18:34:46.418Z",
    "dateUpdated": "2026-08-14T16:50:00.508Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
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.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-R6WG-9VJ9-RM67

CVE-2026-48553 (GCVE-0-2026-48553)

Tags

Sightings

Nomenclature