FKIE_CVE-2026-33897

Vulnerability from fkie_nvd - Published: 2026-03-26 23:16 - Updated: 2026-03-30 18:55
Severity ?
9.9 (Critical) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Summary
Incus is a system container and virtual machine manager. Prior to version 6.23.0, instance template files can be used to cause arbitrary read or writes as root on the host server. Incus allows for pongo2 templates within instances which can be used at various times in the instance lifecycle to template files inside of the instance. This particular implementation of pongo2 within Incus allowed for file read/write but with the expectation that the pongo2 chroot feature would isolate all such access to the instance's filesystem. This was allowed such that a template could theoretically read a file and then generate a new version of said file. Unfortunately the chroot isolation mechanism is entirely skipped by pongo2 leading to easy access to the entire system's filesystem with root privileges. Version 6.23.0 patches the issue.
References
security-advisories@github.comhttps://github.com/lxc/incus/security/advisories/GHSA-83xr-5xxr-mh92Vendor Advisory
Impacted products
Vendor Product Version
linuxcontainers incus *
To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:linuxcontainers:incus:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "CBE3ABCB-1D47-4A45-A09A-C9F609C53131",
              "versionEndExcluding": "6.23.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Incus is a system container and virtual machine manager. Prior to version 6.23.0, instance template files can be used to cause arbitrary read or writes as root on the host server. Incus allows for pongo2 templates within instances which can be used at various times in the instance lifecycle to template files inside of the instance. This particular implementation of pongo2 within Incus allowed for file read/write but with the expectation that the pongo2 chroot feature would isolate all such access to the instance\u0027s filesystem. This was allowed such that a template could theoretically read a file and then generate a new version of said file. Unfortunately the chroot isolation mechanism is entirely skipped by pongo2 leading to easy access to the entire system\u0027s filesystem with root privileges. Version 6.23.0 patches the issue."
    },
    {
      "lang": "es",
      "value": "Incus es un gestor de contenedores de sistema y m\u00e1quinas virtuales. Antes de la versi\u00f3n 6.23.0, los archivos de plantilla de instancia pueden usarse para causar lecturas o escrituras arbitrarias como root en el servidor anfitri\u00f3n. Incus permite plantillas pongo2 dentro de las instancias que pueden usarse en varios momentos del ciclo de vida de la instancia para crear plantillas de archivos dentro de la instancia. Esta implementaci\u00f3n particular de pongo2 dentro de Incus permit\u00eda la lectura/escritura de archivos, pero con la expectativa de que la caracter\u00edstica chroot de pongo2 aislar\u00eda todo ese acceso al sistema de archivos de la instancia. Esto se permit\u00eda de tal manera que una plantilla podr\u00eda te\u00f3ricamente leer un archivo y luego generar una nueva versi\u00f3n de dicho archivo. Desafortunadamente, el mecanismo de aislamiento chroot es completamente omitido por pongo2, lo que lleva a un f\u00e1cil acceso a todo el sistema de archivos del sistema con privilegios de root. La versi\u00f3n 6.23.0 parchea el problema."
    }
  ],
  "id": "CVE-2026-33897",
  "lastModified": "2026-03-30T18:55:33.887",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.9,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 6.0,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-26T23:16:20.743",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://github.com/lxc/incus/security/advisories/GHSA-83xr-5xxr-mh92"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1336"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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