CVE-2026-44829
HighCVSS 8.8Summary
Gotenberg in version 8.32.0 and earlier has a vulnerability in filename handling where filepath.Base on Linux does not treat backslashes as path separators, so a multipart filename containing Windows-style parent directory components survives sanitization. A remote attacker can submit such a name, and when the resulting archive is extracted on a Windows system, files can be written outside the intended directory. This issue is fixed in version 8.33.0.
Risk Assessment
The attack can lead to arbitrary file writes on a downstream Windows system, potentially enabling overwriting sensitive files or malware installation.
Recommendation
Update Gotenberg to version 8.33.0 or later.
Original NVD description (English source)
Gotenberg is a Docker-powered stateless API for PDF files. In 8.32.0 and earlier, filename handling in pkg/modules/api/context.go uses filepath.Base on Linux, which does not treat backslashes as path separators, so a multipart filename containing Windows-style parent directory components survives sanitization. The original filename flows through ctx.diskToOriginal and the multi-output PDF routes into archives.FilesFromDisk and archives.Zip.Archive as the generated zip entry name. A remote attacker can submit a name such as ........\Windows\System32\evil.pdf through an upload or an upstream downloadFrom Content-Disposition header, and a Windows archive extractor can write the resulting file outside the intended extraction directory. The affected paths include /forms/pdfengines/split and other multi-output PDF, LibreOffice, and conversion routes, and exploitation can cause arbitrary file writes on a downstream Windows system when a user or process extracts the returned archive. This issue is fixed in version 8.33.0.