FKIE_CVE-2026-120326

Vulnerability from fkie_nvd - Published: 2026-11-10 12:17 - Updated: 2026-11-10 12:17
Severity
4.8 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N
Summary
DownloadEvent.setFileName(String) in Vaadin Flow writes the download file name into the Content-Disposition header without escaping it. When the name is pure US-ASCII the header is built as attachment; filename="<name>" with the name inserted verbatim, so a double quote in the name ends the quoted string early and the rest of the name is read by the browser as further header parameters. The inline(String) variant, present from Vaadin 25.0, builds the name the same way. An application that passes an untrusted file name to either method, for example when re-serving a file under the name it was uploaded with, lets an attacker add a filename* parameter. Browsers prefer filename* over filename, so the file is saved under a name and extension of the attacker's choosing, which defeats any file name or extension restriction the application enforces. The attacker cannot change the attachment or inline disposition itself and cannot split the header. Users of affected versions should apply the following mitigation or upgrade. Releases that have fixed this issue include: Product version Vaadin 24.8.0 - 24.8.17 Vaadin 24.9.0 - 24.9.25 Vaadin 24.10.0 - 24.10.13 Vaadin 25.0.0 - 25.0.13 Vaadin 25.1.0 - 25.1.13 Vaadin 25.2.0 - 25.2.12 Vaadin 25.3.0 - 25.3.4 Mitigation No fixed release on this line, upgrade to 24.9.26 or newer Upgrade to 24.9.26 Upgrade to 24.10.14 No fixed release on this line, upgrade to 25.2.13 or newer No fixed release on this line, upgrade to 25.2.13 or newer Upgrade to 25.2.13 Upgrade to 25.3.5 Vaadin versions below 24.8 are not affected: the DownloadEvent API does not exist in them.
References
security@vaadin.comhttps://github.com/vaadin/flow/pull/26704
security@vaadin.comhttps://vaadin.com/security/cve-2026-120326
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "com.vaadin:vaadin",
          "product": "vaadin",
          "repo": "https://github.com/vaadin/platform",
          "vendor": "vaadin",
          "versions": [
            {
              "lessThanOrEqual": "24.8.17",
              "status": "affected",
              "version": "24.8.0",
              "versionType": "maven"
            },
            {
              "lessThan": "24.9.26",
              "status": "affected",
              "version": "24.9.0",
              "versionType": "maven"
            },
            {
              "lessThan": "24.10.14",
              "status": "affected",
              "version": "24.10.0",
              "versionType": "maven"
            },
            {
              "lessThanOrEqual": "25.0.13",
              "status": "affected",
              "version": "25.0.0",
              "versionType": "maven"
            },
            {
              "lessThanOrEqual": "25.1.13",
              "status": "affected",
              "version": "25.1.0",
              "versionType": "maven"
            },
            {
              "lessThan": "25.2.13",
              "status": "affected",
              "version": "25.2.0",
              "versionType": "maven"
            },
            {
              "lessThan": "25.3.5",
              "status": "affected",
              "version": "25.3.0",
              "versionType": "maven"
            }
          ]
        },
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "com.vaadin:vaadin-core",
          "product": "vaadin-core",
          "repo": "https://github.com/vaadin/platform",
          "vendor": "vaadin",
          "versions": [
            {
              "lessThanOrEqual": "24.8.17",
              "status": "affected",
              "version": "24.8.0",
              "versionType": "maven"
            },
            {
              "lessThan": "24.9.26",
              "status": "affected",
              "version": "24.9.0",
              "versionType": "maven"
            },
            {
              "lessThan": "24.10.14",
              "status": "affected",
              "version": "24.10.0",
              "versionType": "maven"
            },
            {
              "lessThanOrEqual": "25.0.13",
              "status": "affected",
              "version": "25.0.0",
              "versionType": "maven"
            },
            {
              "lessThanOrEqual": "25.1.13",
              "status": "affected",
              "version": "25.1.0",
              "versionType": "maven"
            },
            {
              "lessThan": "25.2.13",
              "status": "affected",
              "version": "25.2.0",
              "versionType": "maven"
            },
            {
              "lessThan": "25.3.5",
              "status": "affected",
              "version": "25.3.0",
              "versionType": "maven"
            }
          ]
        },
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "com.vaadin:flow-server",
          "product": "flow",
          "repo": "https://github.com/vaadin/flow",
          "vendor": "vaadin",
          "versions": [
            {
              "lessThanOrEqual": "24.8.16",
              "status": "affected",
              "version": "24.8.0",
              "versionType": "maven"
            },
            {
              "lessThan": "24.9.31",
              "status": "affected",
              "version": "24.9.0",
              "versionType": "maven"
            },
            {
              "lessThan": "24.10.17",
              "status": "affected",
              "version": "24.10.0",
              "versionType": "maven"
            },
            {
              "lessThanOrEqual": "25.0.15",
              "status": "affected",
              "version": "25.0.0",
              "versionType": "maven"
            },
            {
              "lessThanOrEqual": "25.1.19",
              "status": "affected",
              "version": "25.1.0",
              "versionType": "maven"
            },
            {
              "lessThan": "25.2.16",
              "status": "affected",
              "version": "25.2.0",
              "versionType": "maven"
            },
            {
              "lessThan": "25.3.6",
              "status": "affected",
              "version": "25.3.0",
              "versionType": "maven"
            }
          ]
        }
      ],
      "source": "security@vaadin.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "DownloadEvent.setFileName(String) in Vaadin Flow writes the download file name into the Content-Disposition header without escaping it. When the name is pure US-ASCII the header is built as attachment; filename=\"\u003cname\u003e\" with the name inserted verbatim, so a double quote in the name ends the quoted string early and the rest of the name is read by the browser as further header parameters. The inline(String) variant, present from Vaadin 25.0, builds the name the same way. An application that passes an untrusted file name to either method, for example when re-serving a file under the name it was uploaded with, lets an attacker add a filename* parameter. Browsers prefer filename* over filename, so the file is saved under a name and extension of the attacker\u0027s choosing, which defeats any file name or extension restriction the application enforces. The attacker cannot change the attachment or inline disposition itself and cannot split the header.\n\nUsers of affected versions should apply the following mitigation or upgrade. Releases that have fixed this issue include:\n\nProduct version\nVaadin 24.8.0 - 24.8.17\nVaadin 24.9.0 - 24.9.25\nVaadin 24.10.0 - 24.10.13\nVaadin 25.0.0 - 25.0.13\nVaadin 25.1.0 - 25.1.13\nVaadin 25.2.0 - 25.2.12\nVaadin 25.3.0 - 25.3.4\n\nMitigation\nNo fixed release on this line, upgrade to 24.9.26 or newer\nUpgrade to 24.9.26\nUpgrade to 24.10.14\nNo fixed release on this line, upgrade to 25.2.13 or newer\nNo fixed release on this line, upgrade to 25.2.13 or newer\nUpgrade to 25.2.13\nUpgrade to 25.3.5\n\nVaadin versions below 24.8 are not affected: the DownloadEvent API does not exist in them."
    }
  ],
  "id": "CVE-2026-120326",
  "lastModified": "2026-11-10T12:17:16.967",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM",
          "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": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "LOW",
          "userInteraction": "ACTIVE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/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": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security@vaadin.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-11-10T12:17:16.837",
  "references": [
    {
      "source": "security@vaadin.com",
      "url": "https://github.com/vaadin/flow/pull/26704"
    },
    {
      "source": "security@vaadin.com",
      "url": "https://vaadin.com/security/cve-2026-120326"
    }
  ],
  "sourceIdentifier": "security@vaadin.com",
  "vulnStatus": "Awaiting Analysis",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-116"
        }
      ],
      "source": "security@vaadin.com",
      "type": "Secondary"
    }
  ]
}



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