FKIE_CVE-2026-8353

Vulnerability from fkie_nvd - Published: 2026-05-22 15:16 - Updated: 2026-07-23 16:10
Severity
4.8 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
Summary
Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation. The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of 2.1 with vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks Yonatan Drori (Tenzai) for reporting.
References
ff5b8ace-8b95-4078-9743-eac1ca5451dehttps://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notesRelease Notes, Vendor Advisory
Impacted products
Vendor Product Version
concretecms concrete_cms *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://github.com/concretecms/concretecms",
          "defaultStatus": "unaffected",
          "product": "Concrete CMS",
          "repo": "https://github.com/concretecms/concretecms",
          "vendor": "Concrete CMS",
          "versions": [
            {
              "lessThanOrEqual": "9.5.0",
              "status": "affected",
              "version": "9.0",
              "versionType": "git"
            }
          ]
        }
      ],
      "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:concretecms:concrete_cms:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F8B152AE-0781-4256-B7C3-4F7B75A83722",
              "versionEndExcluding": "9.5.1",
              "versionStartIncluding": "9.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Concrete CMS version 9.0 to 9.5.0 is vulnerable to Stored XSS via page name in the Atomik theme. A rogue editor\u00a0can inject arbitrary JavaScript that executes in the context of any authenticated user visiting the affected account pages. This can lead to session hijacking, credential theft, malicious actions performed on behalf of users, and potential privilege escalation.\u00a0The Concrete CMS security team gave this vulnerability a CVSS v.4.0 score of\u00a02.1 with vector\u00a0CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks\u00a0Yonatan Drori (Tenzai) for reporting."
    },
    {
      "lang": "es",
      "value": "La versi\u00f3n 9.0 a 9.5.0 de Concrete CMS es vulnerable a XSS Almacenado a trav\u00e9s del nombre de la p\u00e1gina en el tema Atomik. Un editor malicioso puede inyectar JavaScript arbitrario que se ejecuta en el contexto de cualquier usuario autenticado que visita las p\u00e1ginas de cuenta afectadas. Esto puede llevar a secuestro de sesi\u00f3n, robo de credenciales, acciones maliciosas realizadas en nombre de los usuarios y potencial escalada de privilegios. El equipo de seguridad de Concrete CMS otorg\u00f3 a esta vulnerabilidad una puntuaci\u00f3n CVSS v.4.0 de 2.1 con el vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. Gracias a Yonatan Drori (Tenzai) por informar."
    }
  ],
  "id": "CVE-2026-8353",
  "lastModified": "2026-07-23T16:10:00.137",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "HIGH",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 1.7,
        "impactScore": 2.7,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 2.1,
          "baseSeverity": "LOW",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "HIGH",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:L/VI:L/VA:N/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",
          "version": "4.0",
          "vulnAvailabilityImpact": "NONE",
          "vulnConfidentialityImpact": "LOW",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-8353",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-22T17:05:42.901517Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-22T15:16:26.793",
  "references": [
    {
      "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
      "tags": [
        "Release Notes",
        "Vendor Advisory"
      ],
      "url": "https://documentation.concretecms.org/9-x/developers/introduction/version-history/951-release-notes"
    }
  ],
  "sourceIdentifier": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
      "type": "Secondary"
    }
  ]
}



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