Security: Global _blank link rewriting without noopener allows reverse tabnabbing#588
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The script forces all links to open in a new tab by injecting `<base target="_blank">`, but does not enforce `rel="noopener noreferrer"` on those links. Opened pages can access `window.opener` and potentially navigate the original tab to a phishing page (reverse tabnabbing). Affected files: TargetBlank.user.js Signed-off-by: tuanaiseo <221258316+tuanaiseo@users.noreply.github.com>
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Problem
The script forces all links to open in a new tab by injecting
<base target="_blank">, but does not enforcerel="noopener noreferrer"on those links. Opened pages can accesswindow.openerand potentially navigate the original tab to a phishing page (reverse tabnabbing).Severity:
mediumFile:
TargetBlank.user.jsSolution
Avoid global
<base target="_blank">for untrusted destinations, or explicitly setrel="noopener noreferrer"on every external link opened in a new tab. Prefer per-link handling with strict URL checks.Changes
TargetBlank.user.js(modified)Testing