Merge pull request from GHSA-ccm4-vgcc-73hp

* Tighten allowed HTML in oEmbed-based preview cards

* Sanitize preview cards at render time

* Add `sandbox` attribute to preview card iframes
This commit is contained in:
Claire 2023-07-06 15:03:33 +02:00 committed by GitHub
parent 9b6c0cac7d
commit c4f2609f7a
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2 changed files with 15 additions and 11 deletions

View file

@ -11,4 +11,8 @@ class REST::PreviewCardSerializer < ActiveModel::Serializer
def image def image
object.image? ? full_asset_url(object.image.url(:original)) : nil object.image? ? full_asset_url(object.image.url(:original)) : nil
end end
def html
Sanitize.fragment(object.html, Sanitize::Config::MASTODON_OEMBED)
end
end end

View file

@ -94,26 +94,26 @@ class Sanitize
] ]
) )
MASTODON_OEMBED ||= freeze_config merge( MASTODON_OEMBED ||= freeze_config(
RELAXED, elements: %w(audio embed iframe source video),
elements: RELAXED[:elements] + %w(audio embed iframe source video),
attributes: merge( attributes: {
RELAXED[:attributes],
'audio' => %w(controls), 'audio' => %w(controls),
'embed' => %w(height src type width), 'embed' => %w(height src type width),
'iframe' => %w(allowfullscreen frameborder height scrolling src width), 'iframe' => %w(allowfullscreen frameborder height scrolling src width),
'source' => %w(src type), 'source' => %w(src type),
'video' => %w(controls height loop width), 'video' => %w(controls height loop width),
'div' => [:data] },
),
protocols: merge( protocols: {
RELAXED[:protocols],
'embed' => { 'src' => HTTP_PROTOCOLS }, 'embed' => { 'src' => HTTP_PROTOCOLS },
'iframe' => { 'src' => HTTP_PROTOCOLS }, 'iframe' => { 'src' => HTTP_PROTOCOLS },
'source' => { 'src' => HTTP_PROTOCOLS } 'source' => { 'src' => HTTP_PROTOCOLS },
) },
add_attributes: {
'iframe' => { 'sandbox' => 'allow-scripts allow-same-origin allow-popups allow-popups-to-escape-sandbox allow-forms' },
}
) )
end end
end end