Unsafe Cross-Origin Links Test: Catch target=_blank Without noopener

If you are searching for unsafe cross origin links, you usually mean one specific pattern: an external target="_blank" link that is missing rel="noopener" (and ideally rel="noreferrer"). That markup looks harmless. It is the default habit of “open this in a new tab.” Without the right rel values, the new tab can keep a reference back to your page—and that is where reverse tabnabbing and opener-based phishing begin.

Site Signals has a free check for exactly that. Paste a live URL into the Unsafe Cross-Origin Links Test, run it, and see which target="_blank" links are missing the protection modern link hygiene expects.

What “unsafe cross-origin links” actually means

When a visitor clicks a link with target="_blank", the browser opens a new browsing context. Historically, that new page received a window.opener handle pointing at your tab. From there, the destination could:

• Call window.opener.location and replace your tab with a lookalike phishing page (classic reverse tabnabbing).
• Keep a live reference into your origin’s window object longer than you intended.
• Share more browsing-context coupling than a normal same-tab navigation would.

Modern browsers have tightened defaults for target="_blank", and many frameworks now emit rel="noopener" automatically. That does not retire the audit. Legacy templates, CMS widgets, affiliate modules, social share plugins, and hand-written HTML still ship bare target="_blank" links. Partners and third-party embeds can reintroduce the pattern after a redesign. If you care about security hygiene on external outbound links, you still need to inventory them.

rel="noopener" tells the browser not to set window.opener on the new context. rel="noreferrer" includes that protection and also suppresses the Referer header on the navigation. For public marketing sites, the practical fix for external new-tab links is almost always:

<a href="https://example.com" target="_blank" rel="noopener noreferrer">Example</a>

Why this matters for SEO and security teams together

This is not a Core Web Vitals metric. It is still a conversion and trust problem. Users who leave your site through an unsafe new-tab link and land back on a spoofed “re-login” page blame your brand, not the destination. Security reviews, pen-test write-ups, and enterprise procurement questionnaires often flag missing noopener on outbound links. Clean markup also signals disciplined template control—the same discipline that keeps canonical tags, noindex rules, and robots.txt coherent.

From an SEO operations angle, unsafe cross-origin links usually cluster in a few places:

• Blog footers and “read more” modules that force new tabs for every external citation.
• Partner / sponsor / affiliate blocks pasted by non-engineering editors.
• Share buttons and “open documentation” CTAs in product UI.
• Older WordPress or custom themes that never updated link helpers after browser defaults changed.

Finding them by eye does not scale. A page-level scan that lists every target="_blank" candidate and flags missing rel protection does.

How to fix unsafe target=_blank links

Once you know which URLs are exposed, the remediation is straightforward:

1. Prefer same-tab navigation when a new tab is not required. Drop target="_blank" entirely for internal links and for many editorial citations.
2. When you must open a new tab for an external destination, add rel="noopener noreferrer".
3. Fix the template, not one page. Patch the link helper, CMS filter, or component that emits anchors so every future link inherits the safe defaults.
4. Re-scan after deploy. Confirm the flagged URLs clear, then spot-check high-traffic templates (home, pricing, blog post, resource hub).

If your stack already injects noopener, treat remaining failures as exceptions: third-party HTML, raw CMS fields, or hard-coded marketing landing pages that bypass the component library.

Run the free Unsafe Cross-Origin Links Test

Open the Unsafe Cross-Origin Links Test on tools.positionmysite.com. The tool page title is “Unsafe Cross-Origin Links Test | rel=noopener Audit.” You do not need an account.

1. Paste a full production URL (homepage, article, or high-exit landing page).
2. Click Run Free Test.
3. Read the Unsafe Cross-Origin Signal Analysis: which target="_blank" links lack rel="noopener" / rel="noreferrer", and whether the page passes overall.

Use it on the pages that send the most traffic to third parties—resource roundups, comparison posts, partner directories, and checkout-adjacent help links. Those are where tabnabbing risk and brand trust collide. After you patch templates, run the same URLs again so engineering and SEO share one pass/fail artifact instead of a spreadsheet of “we think we fixed it.”

What a clean result should look like

A passing page reports that external target="_blank" links are secured with noopener or noreferrer. A failing page lists the offenders so you can map them back to a template or CMS field. Either way, you leave with a concrete punch list—not a vague warning to “be careful with external links.”

Pair this audit with your normal release checklist: when you ship a new footer, affiliate module, or “open docs” pattern, re-run the test on a staging or production URL before you call the release done. That habit costs seconds and prevents the class of issue that only shows up after a security review or a phishing report.

Practical workflow for teams

Give SEO or content ops the free tool URL. Have them sample the top external-link pages each month. Engineering owns the shared link component. Marketing owns one-off landing pages that skip the design system. When Search Console or your analytics show a surge of exits to a new partner domain, scan those templates first—new partnerships are a common source of fresh bare target="_blank" markup.

Teaching editors to check their own outbound-link patterns in staging is fine. Publishing your own raw Search Console counts in a blog post is not useful to the reader and is not how this guide works. What helps is a repeatable test they can run on their URLs.

Start with one live URL

You do not need a full crawl to get value. Pick the page that opens the most partner or documentation links in new tabs. Run the Unsafe Cross-Origin Links Test, fix the template that emitted the unsafe anchors, and re-test. That single loop—detect, patch, confirm—is how unsafe cross origin links stop being a lingering hygiene debt and become a closed ticket.