What causes "error validating file path (%s, %s): %w" in apache/beam?

Stop using this jar; it failed the safe-extraction check.

error validating file path

Error message

error validating file path (%s, %s): %w

What it means

While iterating zip entries, extractJar calls validatePath(dest, file.Name) for every entry; this error wraps any path-validation failure with the destination and the offending entry name for context. It is the extractJar-level wrapper around the Zip Slip protection: an entry in the jar resolves outside the destination directory and cannot be safely extracted.

Solutions

Stop using this jar; it failed the safe-extraction check.
Identify the offending entry from the wrapped filename in the message.
Re-obtain the jar from the official artifact repository.
Rebuild the jar with relative entry paths if you control its creation.

Defensive patterns

Strategy: validation

Validate before calling

// Reject jars containing traversal entries before invoking extraction
r, err := zip.OpenReader(jarPath)
if err != nil { return err }
for _, f := range r.File {
    if strings.Contains(f.Name, "..") || filepath.IsAbs(f.Name) {
        return fmt.Errorf("jar contains unsafe entry %q", f.Name)
    }
}

Try / catch

err := expansionx.MakeJar(ctx, url, dest)
if err != nil && strings.Contains(err.Error(), "error validating file path") {
    os.Remove(jarPath)
    return fmt.Errorf("unsafe jar from %s rejected", url)
}

Prevention

Source jars only from trusted, checksum-verified repositories.
Scan archive entry names for traversal patterns before use.
Treat validation failures as supply-chain incidents, not retryable errors.
Keep jar provenance (URL + checksum) recorded per pipeline.

When it happens

Trigger: An entry name in the jar contains ../ traversal segments, an absolute path, or otherwise fails filepath.Rel containment check during extractJar.

Common situations: A malicious or corrupted expansion-service jar; jars generated by tooling that wrote absolute entry paths; manually edited jars.

Understand the failure class

Background: Path traversal blocked: "path escapes the workspace" and "outside site root" errors when a path will not stay inside its allowed directory — this error's family across 26 libraries.

Related errors

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/6c9b445f1672cccd. Report an issue: GitHub.

Appendix: source

Thrown at sdks/go/pkg/beam/core/runtime/xlangx/expansionx/download.go:167

		return "", fmt.Errorf("file path %q is outside destination directory %q", filename, dest)
	}
	return cleanPath, nil
}

func extractJar(source, dest string) error {
	reader, err := zip.OpenReader(source)
	if err != nil {
		return fmt.Errorf("error opening jar for extractJar(%s,%s): %w", source, dest, err)
	}

	if err := os.MkdirAll(dest, 0700); err != nil {
		return fmt.Errorf("error creating directory %s in extractJar(%s,%s): %w", dest, source, dest, err)
	}

	for _, file := range reader.File {
		fileName, err := validatePath(dest, file.Name)
		if err != nil {
			return fmt.Errorf("error validating file path (%s, %s): %w", dest, file.Name, err)
		}
		if file.FileInfo().IsDir() {
			os.MkdirAll(fileName, 0700)
			continue
		}

		sf, err := file.Open()
		if err != nil {
			return fmt.Errorf("error opening source file %s: %w", file.Name, err)
		}
		defer sf.Close()

		df, err := os.OpenFile(fileName, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0777)
		if err != nil {
			return fmt.Errorf("error opening destination file %s: %w", fileName, err)
		}
		defer df.Close()

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