WebP Server Go < 0.15.0 Path Traversal via Backslash Encoding on Windows

{
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "cveMetadata": {
    "cveId": "CVE-2026-53779",
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "dateUpdated": "2026-06-22T18:23:07.076Z",
    "dateReserved": "2026-06-10T20:14:32.826Z",
    "datePublished": "2026-06-22T18:22:40.698Z",
    "state": "PUBLISHED"
  },
  "containers": {
    "cna": {
      "providerMetadata": {
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck",
        "dateUpdated": "2026-06-22T18:23:07.076Z"
      },
      "datePublic": "2026-06-03T00:00:00.000Z",
      "title": "WebP Server Go < 0.15.0 Path Traversal via Backslash Encoding on Windows",
      "descriptions": [
        {
          "lang": "en",
          "value": "WebP Server Go through 0.14.4 contains a path traversal vulnerability on Windows that allows unauthenticated attackers to read files outside the configured IMG_PATH directory by sending requests with percent-encoded backslashes (%5C) that bypass the path.Clean() sanitization in handler/router.go. Attackers can exploit the discrepancy between Go's forward-slash-only path normalization and Windows file system APIs that treat backslashes and forward slashes as equivalent to access arbitrary files on the host filesystem accessible to the server process."
        }
      ],
      "affected": [
        {
          "vendor": "webp-sh",
          "product": "webp_server_go",
          "repo": "https://github.com/webp-sh/webp_server_go",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "0",
              "status": "affected",
              "versionType": "semver",
              "lessThan": "0.15.0"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "lang": "en",
              "description": "Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')",
              "cweId": "CWE-22",
              "type": "CWE"
            }
          ]
        }
      ],
      "references": [
        {
          "url": "https://github.com/webp-sh/webp_server_go/pull/451",
          "name": "Pull Request",
          "tags": [
            "issue-tracking"
          ]
        },
        {
          "url": "https://github.com/webp-sh/webp_server_go/commit/eb3b5f9289b331cb639cd610b0d1c532d2cc24e0",
          "name": "Patch Commit",
          "tags": [
            "patch"
          ]
        },
        {
          "url": "https://www.vulncheck.com/advisories/webp-server-go-path-traversal-via-backslash-encoding-on-windows",
          "tags": [
            "third-party-advisory"
          ]
        }
      ],
      "metrics": [
        {
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        },
        {
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ],
          "cvssV3_1": {
            "version": "3.1",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
            "attackVector": "NETWORK",
            "attackComplexity": "LOW",
            "privilegesRequired": "NONE",
            "userInteraction": "NONE",
            "scope": "UNCHANGED",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "availabilityImpact": "NONE",
            "baseScore": 7.5,
            "baseSeverity": "HIGH"
          }
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Katriel Moses",
          "type": "reporter"
        }
      ],
      "tags": [
        "x_open-source"
      ]
    }
  }
}