fix: escape HTML content before embedding in JavaScript string in editor_insert_html#1329
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karlkleinpaste merged 1 commit intoJun 19, 2026
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…tor_insert_html
editor_insert_html() embeds user-controlled HTML (e.g. the link text from
the link dialog) into a JavaScript string literal that is then executed via
webkit_web_view_execute_script():
document.execCommand('insertHTML', null, '%s');
Neither single quotes nor backslashes were escaped, so a single quote in the
input broke out of the JS string and allowed arbitrary script execution in
the editor's WebKit context.
Escape the content with g_strescape() before embedding. g_strescape()
escapes backslashes, double quotes and control characters, but it does NOT
escape single quotes -- so the JS string literal is changed from
single-quoted to double-quoted to match what g_strescape() actually escapes.
This blocks both ' and " breakout while preserving legitimate HTML markup
(e.g. quoted href attributes).
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editor_insert_html() embeds user-controlled HTML (e.g. the link text
from the link dialog) into a JavaScript string literal that is then
executed via webkit_web_view_execute_script():
Neither single quotes nor backslashes were escaped, so a single quote
in the input broke out of the JS string and allowed arbitrary script
execution in the editor's WebKit context.
Escape the content with g_strescape() before embedding. g_strescape()
escapes backslashes, double quotes and control characters, but it does
NOT escape single quotes -- so the JS string literal is changed from
single-quoted to double-quoted to match what g_strescape() actually
escapes. This blocks both ' and " breakout while preserving legitimate
HTML markup (e.g. quoted href attributes).