A security issue has been found in Firefox before 69.0. Some HTML elements, such as <title> and <textarea>, can contain literal angle brackets without treating them as markup. It is possible to pass a literal closing tag to .innerHTML on these elements, and subsequent content after that will be parsed as if it were outside the tag. This can lead to XSS if a site does not filter user input as strictly for these elements as it does for other elements.
A security issue has been found in Firefox before 69.0. Some HTML elements, such as <title> and <textarea>, can contain literal angle brackets without treating them as markup. It is possible to pass a literal closing tag to .innerHTML on these elements, and subsequent content after that will be parsed as if it were outside the tag. This can lead to XSS if a site does not filter user input as strictly for these elements as it does for other elements.
https://www.mozilla.org/en-US/security/advisories/mfsa2019-25/#CVE-2019-11744 https://bugzilla.mozilla.org/show_bug.cgi?id=1562033
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