Tab character bypasses javascript: URL protocol removal in Firefox < 59

CVE-2018-5143 · MEDIUM Severity

AV:N/AC:M/AU:N/C:N/I:P/A:N

URLs using "javascript:" have the protocol removed when pasted into the addressbar to protect users from cross-site scripting (XSS) attacks, but if a tab character is embedded in the "javascript:" URL the protocol is not removed and the script will execute. This could allow users to be socially engineered to run an XSS attack against themselves. This vulnerability affects Firefox < 59.

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