fix: escape comment content that abruptly closes the comment - #40
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Escape a leading `>` or `->` in comment data during HTML serialization, so
that `#comment('><img src=x onerror=xss()>')` is emitted as
`<!--><img src=x onerror=xss()>-->` rather than
`<!--><img src=x onerror=xss()>-->`.
The parser treats `>` and `->` immediately after `<!--` as an
abrupt-closing-of-empty-comment parse error and emits the comment right
away, so everything that followed was parsed as live markup. An inert
comment node therefore became an XSS vector once an SSR response was
de-serialized by the browser.
Closes angular/angular#70439
SkyZeroZx
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Escape a leading
>or->in comment data during HTML serialization, so that#comment('><img src=x onerror=xss()>')is emitted as<!--><img src=x onerror=xss()>-->rather than<!--><img src=x onerror=xss()>-->.The parser treats
>and->immediately after<!--as an abrupt-closing-of-empty-comment parse error and emits the comment right away, so everything that followed was parsed as live markup. An inert comment node therefore became an XSS vector once an SSR response was de-serialized by the browser.Closes angular/angular#70439