Path Traversal in github.com/gotenberg/gotenberg/v8 (CVE-2026-44829)
Summary
Path traversal in github.com/gotenberg/gotenberg/v8 (CVE-2026-44829). Data can be tampered with by attackers. Exploitable via filepath.Base. Mitigation: upgrade to 8.33.0 or later.
Original description
The description as published by the source.
Summary
filepath.Base on the Linux container does not strip backslashes (\), because \ is only a path separator on Windows. A multipart filename like ..\..\..\..\Windows\System32\evil.pdf survives Gotenberg's input sanitisation and lands verbatim as the zip entry name when a multi-output route returns its result as a zip (e.g. /forms/pdfengines/split). Windows zip extractors interpret \ as a path separator and write the file outside the extraction directory.
Details
pkg/modules/api/context.go:434, 472:
filename := norm.NFC.String(filepath.Base(fh.Filename))
On Linux, filepath.Base("..\\..\\..\\..\\Windows\\System32\\evil.pdf") returns the same string verbatim — there are no / separators to find. The original filename then flows to ctx.diskToOriginal (pkg/modules/api/context.go:459, 393) and through pkg/modules/pdfengines/routes.go:287-322 (SplitPdfStub), which builds:
originalNameNoExt := strings.TrimSuffix(originalName, filepath.Ext(originalName))
newOriginal := fmt.Sprintf("%s_%d.pdf", originalNameNoExt, i)
ctx.RegisterDiskPath(newPath, newOriginal)
Finally pkg/modules/api/context.go:617-642 constructs the zip via archives.FilesFromDisk + archives.Zip{}.Archive. mholt/archives@v0.1.5/archives.go:155-184 (nameOnDiskToNameInArchive) returns path.Join(rootInArchive, "") — the map value verbatim.
Suggested fix
- filename := norm.NFC.String(filepath.Base(fh.Filename))
+ filename := sanitizeFilen…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-44829 has been found in github.com/gotenberg/gotenberg/v8.
Attackers can target a specific entry point like filepath.Base over the network to misuse the product.
Data can be tampered with by attackers. CVSS score: 8.8/10.
What to do: upgrade github.com/gotenberg/gotenberg/v8 to 8.33.0 or later.
If unsure, ask your IT team or search "github.com/gotenberg/gotenberg/v8 CVE-2026-44829" on the vendor's site.
CVE-2026-44829 (github.com/gotenberg/gotenberg/v8) — CWE-22 / CVSS v3 8.8
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: filepath.Base / ctx.diskToOriginal / SplitPdfStub / archives.FilesFromDisk
Patched: 8.33.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Path traversal (CWE-22) exists in github.com/gotenberg/gotenberg/v8. Attackers reach the vulnerable code path via filepath.Base without authentication.
Check the vendor advisory for the affected versions of github.com/gotenberg/gotenberg/v8. Attack surface: filepath.Base / ctx.diskToOriginal / SplitPdfStub / archives.FilesFromDisk.
Severity: High (CVSS 8.8/10). Data can be tampered with by attackers.
Update to 8.33.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/gotenberg/gotenberg/v8' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/gotenberg/gotenberg/v8' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/gotenberg/gotenberg/v8を grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade github.com/gotenberg/gotenberg/v8 to 8.33.0ステージング環境で 8.33.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。