DOM Clobbering strikes back
Summary: PortSwigger researcher Gareth Heyes revisits DOM Clobbering, a technique he first introduced in 2013, noting that as XSS and CSRF get patched and constrained by CSP and SameSite, niche client-side techniques are becoming more relevant. He cites Michał Bentkowski's use of DOM Clobbering to exploit GMail six years after the original research, and presents new techniques including three-level clobbering with DOM collections and forms, clobbering via iframes and srcdoc, and a no-timeout iframe method that relies on a stylesheet import delay.
Why it matters: The GMail exploit shows a technique first published in 2013 still landing on a major webmail product six years later, which means defenses that closed off XSS and CSRF may leave this class of attack untouched in your own applications.
Read the original at PortSwigger Research ↗
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- Vulnerabilities & Patching
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