CVE-2026-44829Gotenberg: Path traversal in zip entry name via Windows-style separators in upload filename

Official description

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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://github.com/gotenberg/gotenberg/security/advisories/GHSA-hwc4-gmrw-5222 x_refsource_CONFIRM
• https://github.com/gotenberg/gotenberg/issues/662 x_refsource_MISC
• https://github.com/gotenberg/gotenberg/commit/93d0103585372433e18b351bb16edf4c383932d3 x_refsource_MISC
• https://github.com/gotenberg/gotenberg/releases/tag/v8.33.0 x_refsource_MISC