CSS is a stylesheet language which provides a presentation for documents, all our modern websites heavily depend on the CSS. A new CSS vulnerability dubbed CSS Exfil can be used by attackers to steal data from the webpages using CSS.
With the vulnerability, attackers can steal sensitive data’s including usernames, passwords, and sensitive data such as date of birth, social security numbers, and credit card numbers. Also, this method can de-anonymize Tor users.
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