projectdiscovery/katana · info

ErrOutOfScope

ErrOutOfScope

Error message

out of scope

What it means

ErrOutOfScope is a sentinel error in katana's common engine package indicating a request was not visited because its URL falls outside the configured crawl scope. Instead of being enqueued, out-of-scope requests are sent directly to output with this error attached. It signals intentional filtering, not a runtime failure.

Source

Thrown at pkg/engine/common/error.go:5

package common

import "errors"

var ErrOutOfScope = errors.New("out of scope")
var ErrMaxDepthReached = errors.New("max depth reached")

View on GitHub (pinned to e3e742739c)

Solutions

1. Verify the URL is genuinely out of scope; if it should be crawled, widen scope with -d / -c / scope filters or use 'in-scope' regex options
2. Set Options.Options.DisplayOutScope only when diagnostics on skipped URLs are desired
3. Compare the error against common.ErrOutOfScope (errors.Is) to filter it from real failures in custom output writers

Example fix

// before: treating every writer error as fatal
if result.Error != "" { return fmt.Errorf("crawl failed: %s", result.Error) }
// after
if errors.Is(err, common.ErrOutOfScope) { return nil } // expected scope filtering

u, err := url.Parse(targetURL)
if err != nil { return err }
if !scopeMatcher.Match(u) { // pre-check against scope regexes
    return nil // skip before Enqueue
}

func isOutOfScope(err error) bool { return errors.Is(err, common.ErrOutOfScope) }

if result.Error != "" {
    if errors.Is(err, common.ErrOutOfScope) {
        return nil // expected, ignore
    }
    return err
}

When it happens

Trigger: Enqueue receives a request whose URL does not match the scope rules (-d domain, scope filters, field-scope); with Options.DisplayOutScope set, the request is passed to s.Output(nr, nil, ErrOutOfScope) at pkg/engine/common/base.go:160 and skipped from the queue.

Common situations: Crawling with -d example.com and encountering links to cdn.example.org or third-party sites; using a custom scope filter that is stricter than expected; enabling display-out-scope and mistaking these output entries for crawl errors.

Related errors

• ErrMaxDepthReached
• ErrNoCrawlingAction
• unknown action type: %v
• failed to get origin page state: %w
• failed to navigate back to origin page: %s != %s

AI-assisted analysis of projectdiscovery/katana@e3e742739c (2026-09-03). Data as JSON: /api/errors/75217d1f8720dd2c. Report an issue: GitHub.