FKIE_CVE-2026-28499

Vulnerability from fkie_nvd - Published: 2026-03-18 02:16 - Updated: 2026-06-17 10:28
Severity
6.1 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Summary
LeafKit is a templating language with Swift-inspired syntax. Prior to version 1.14.2, HTML escaping doesn't work correctly when a template prints a collection (Array / Dictionary) via `#(value)`. This can result in XSS, allowing potentially untrusted input to be rendered unescaped. Version 1.14.2 fixes the issue.
References
security-advisories@github.comhttps://github.com/vapor/leaf-kit/commit/6044b844caa858a0c5f2505ac166f5a057c990dcPatch
security-advisories@github.comhttps://github.com/vapor/leaf-kit/releases/tag/1.14.2Release Notes
security-advisories@github.comhttps://github.com/vapor/leaf-kit/security/advisories/GHSA-6jj5-j4j8-8473Exploit, Vendor Advisory
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/vapor/leaf-kit/security/advisories/GHSA-6jj5-j4j8-8473Exploit, Vendor Advisory
Impacted products
Vendor Product Version
vapor leafkit *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "leaf-kit",
          "vendor": "vapor",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 1.14.2"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:vapor:leafkit:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "C8687D7A-0F30-464E-8F28-21C4B1B29F0D",
              "versionEndExcluding": "1.14.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "LeafKit is a templating language with Swift-inspired syntax. Prior to version 1.14.2, HTML escaping doesn\u0027t work correctly when a template prints a collection (Array / Dictionary) via `#(value)`. This can result in XSS, allowing potentially untrusted input to be rendered unescaped. Version 1.14.2 fixes the issue."
    },
    {
      "lang": "es",
      "value": "LeafKit es un lenguaje de plantillas con sintaxis inspirada en Swift. Antes de la versi\u00f3n 1.14.2, el escape de HTML no funciona correctamente cuando una plantilla imprime una colecci\u00f3n (Array / Dictionary) a trav\u00e9s de `#(value)`. Esto puede resultar en XSS, permitiendo que la entrada potencialmente no confiable se renderice sin escape. La versi\u00f3n 1.14.2 soluciona el problema."
    }
  ],
  "id": "CVE-2026-28499",
  "lastModified": "2026-06-17T10:28:45.043",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 6.1,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "NONE",
          "scope": "CHANGED",
          "userInteraction": "REQUIRED",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 2.7,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 6.9,
          "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": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "LOW",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/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": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-28499",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-03-18T14:08:03.027830Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-03-18T02:16:24.060",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/vapor/leaf-kit/commit/6044b844caa858a0c5f2505ac166f5a057c990dc"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Release Notes"
      ],
      "url": "https://github.com/vapor/leaf-kit/releases/tag/1.14.2"
    },
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/vapor/leaf-kit/security/advisories/GHSA-6jj5-j4j8-8473"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "tags": [
        "Exploit",
        "Vendor Advisory"
      ],
      "url": "https://github.com/vapor/leaf-kit/security/advisories/GHSA-6jj5-j4j8-8473"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        },
        {
          "lang": "en",
          "value": "CWE-80"
        },
        {
          "lang": "en",
          "value": "CWE-116"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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