Mythic 3.2.16 through 3.4.0.61 Stored XSS via Agent-Downloaded File Preview

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-119764",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-10-30T17:19:55.892Z",
    "dateReserved": "2026-10-30T15:36:24.107Z",
    "datePublished": "2026-10-30T17:19:55.892Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck",
        "dateUpdated": "2026-10-30T17:19:55.892Z"
      },
      "datePublic": "2026-10-02T00:00:00.000Z",
      "title": "Mythic 3.2.16 through 3.4.0.61 Stored XSS via Agent-Downloaded File Preview",
      "descriptions": [
        {
          "lang": "en",
          "value": "Mythic 3.2.16 through 3.4.0.61 contains a stored cross-site scripting vulnerability that allows attackers controlling target endpoint files to run JavaScript in the Mythic UI origin by planting HTML in .pdf-named files. When an operator downloads the file and clicks Preview Media, content-sniffed HTML from /direct/view renders same-origin, stealing localStorage JWTs for full GraphQL and REST access."
        }
      ],
      "affected": [
        {
          "vendor": "its-a-feature",
          "product": "Mythic",
          "repo": "https://github.com/its-a-feature/Mythic",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "3.2.16",
              "status": "affected",
              "versionType": "custom",
              "lessThanOrEqual": "3.4.0.61"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
              "cweId": "CWE-79",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/h00die/mythic_xss",
          "tags": [
            "third-party-advisory"
          ]
        },
        {
          "url": "https://github.com/its-a-feature/Mythic/commit/f06b3ed2d1de6577744cc0b3146966c625685859",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://github.com/its-a-feature/Mythic/blob/33a46d7db7e237458d7e20e7d3cfefef8112e590/MythicReactUI/src/components/pages/Callbacks/ResponseDisplayMedia.js#L335-L336",
          "tags": [
            "technical-description"
          ]
        },
        {
          "url": "https://github.com/its-a-feature/Mythic",
          "tags": [
            "product"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/mythic-3.2.16-through-3.4.0.61-stored-xss-via-agent-downloaded-file-preview",
          "name": "VulnCheck Advisory: Mythic 3.2.16 through 3.4.0.61 Stored XSS via Agent-Downloaded File Preview",
          "tags": [
            "third-party-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS"
        },
        {
          "format": "CVSS",
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
            "attackVector": "NETWORK",
            "attackComplexity": "HIGH",
            "privilegesRequired": "NONE",
            "userInteraction": "REQUIRED",
            "scope": "UNCHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "availabilityImpact": "NONE",
            "baseScore": 6.8,
            "baseSeverity": "MEDIUM"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "h00die",
          "type": "finder"
        }
      ]
    }
  }
}