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FKIE_CVE-2025-15265

Vulnerability from fkie_nvd - Published: 2026-01-15 20:16 - Updated: 2026-06-17 08:37
Severity
6.1 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Summary
An SSR XSS exists in async hydration when attacker‑controlled keys are passed to hydratable. The key is embedded inside a <script> block without HTML‑safe escaping, allowing </script> to terminate the script and inject arbitrary JavaScript. This enables remote script execution in users' browsers, with potential for session theft and account compromise. This issue affects Svelte: from 5.46.0 before 5.46.3.
References
help@fluidattacks.comhttps://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
help@fluidattacks.comhttps://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
help@fluidattacks.comhttps://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
help@fluidattacks.comhttps://fluidattacks.com/advisories/lydianExploit, Third Party Advisory
help@fluidattacks.comhttps://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3Third Party Advisory
Impacted products
Vendor Product Version
svelte svelte *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://registry.npmjs.org",
          "defaultStatus": "unaffected",
          "packageName": "svelte",
          "platforms": [
            "Windows",
            "Linux",
            "MacOS"
          ],
          "product": "Svelte",
          "vendor": "Svelte",
          "versions": [
            {
              "lessThan": "5.46.3",
              "status": "affected",
              "version": "5.46.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "help@fluidattacks.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:svelte:svelte:*:*:*:*:*:node.js:*:*",
              "matchCriteriaId": "388FECC8-EDAB-4046-96F5-AC7087330E95",
              "versionEndExcluding": "5.46.3",
              "versionStartIncluding": "5.46.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An SSR XSS exists in async hydration when attacker\u2011controlled keys are passed to hydratable. The key is embedded inside a \u003cscript\u003e block without HTML\u2011safe escaping, allowing \u003c/script\u003e to terminate the script and inject arbitrary JavaScript. This enables remote script execution in users\u0027 browsers, with potential for session theft and account compromise.\nThis issue affects Svelte: from 5.46.0 before 5.46.3."
    },
    {
      "lang": "es",
      "value": "Existe una vulnerabilidad de tipo SSR XSS en la hidrataci\u00f3n as\u00edncrona cuando se pasan claves controladas por el atacante a `hydratable`. La clave se incrusta dentro de un bloque `` termine el script e inyecte c\u00f3digo JavaScript arbitrario. Esto permite la ejecuci\u00f3n remota de scripts en los navegadores de los usuarios, con el riesgo de robo de sesi\u00f3n y compromiso de la cuenta. Este problema afecta a Svelte: desde la versi\u00f3n 5.46.0 hasta la 5.46.3."
    }
  ],
  "id": "CVE-2025-15265",
  "lastModified": "2026-06-17T08:37:29.597",
  "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": 5.3,
          "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": "LOW",
          "userInteraction": "PASSIVE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/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": "help@fluidattacks.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-15265",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-01-15T20:28:05.329081Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-01-15T20:16:03.490",
  "references": [
    {
      "source": "help@fluidattacks.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://fluidattacks.com/advisories/lydian"
    },
    {
      "source": "help@fluidattacks.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://fluidattacks.com/advisories/lydian"
    },
    {
      "source": "help@fluidattacks.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://fluidattacks.com/advisories/lydian"
    },
    {
      "source": "help@fluidattacks.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ],
      "url": "https://fluidattacks.com/advisories/lydian"
    },
    {
      "source": "help@fluidattacks.com",
      "tags": [
        "Third Party Advisory"
      ],
      "url": "https://github.com/sveltejs/svelte/security/advisories/GHSA-6738-r8g5-qwp3"
    }
  ],
  "sourceIdentifier": "help@fluidattacks.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "help@fluidattacks.com",
      "type": "Secondary"
    }
  ]
}



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