WebP Server Go < 0.15.0 Path Traversal via Backslash Encoding on Windows_CVE-2026-53779

{
    "lastseen": "",
    "description": "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.",
    "published": "2026-06-22T18:22:40.698Z",
    "modified": "2026-06-22T18:23:07.076Z",
    "type": "cve",
    "title": "WebP Server Go < 0.15.0 Path Traversal via Backslash Encoding on Windows",
    "source": "VulnCheck",
    "references": "https://github.com/webp-sh/webp_server_go/pull/451\nhttps://github.com/webp-sh/webp_server_go/commit/eb3b5f9289b331cb639cd610b0d1c532d2cc24e0\nhttps://www.vulncheck.com/advisories/webp-server-go-path-traversal-via-backslash-encoding-on-windows",
    "id": "CVE-2026-53779",
    "bulletinFamily": "",
    "cwe": [
        "CWE-22"
    ],
    "cvelist": null,
    "sourceData": "webp-sh webp_server_go 0",
    "sourceHref": "",
    "cvss": {
        "score": 8.7,
        "severity": "HIGH",
        "vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
        "version": "4.0"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "webp_server_go",
    "version": "0",
    "vendor": "webp-sh",
    "ai_description": "Path traversal vulnerability in WebP Server Go on Windows via backslash encoding",
    "ai_severity": "High",
    "ai_vendor": "webp-sh",
    "ai_product": "WebP Server Go",
    "ai_version": "0.14.4",
    "ai_score": 8.7
}