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fix incorrect ^$ usage leading to XSS in sanitize_css [CVE-2013-1855]

Conflicts:
	actionpack/lib/action_controller/vendor/html-scanner/html/sanitizer.rb
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charliesome authored and tenderlove committed Feb 12, 2013
1 parent ef9f053 commit f67851a6b35d930f632188d2734f95b3d0d37a2b
@@ -106,8 +106,8 @@ def sanitize_css(style)
style = style.to_s.gsub(/url\s*\(\s*[^\s)]+?\s*\)\s*/, ' ')

# gauntlet
if style !~ /^([:,;#%.\sa-zA-Z0-9!]|\w-\w|\'[\s\w]+\'|\"[\s\w]+\"|\([\d,\s]+\))*$/ ||
style !~ /^(\s*[-\w]+\s*:\s*[^:;]*(;|$)\s*)*$/
if style !~ /\A([:,;#%.\sa-zA-Z0-9!]|\w-\w|\'[\s\w]+\'|\"[\s\w]+\"|\([\d,\s]+\))*\z/ ||
style !~ /\A(\s*[-\w]+\s*:\s*[^:;]*(;|$)\s*)*\z/
return ''
end

@@ -117,8 +117,8 @@ def sanitize_css(style)
clean << prop + ': ' + val + ';'
elsif shorthand_css_properties.include?(prop.split('-')[0].downcase)
unless val.split().any? do |keyword|
!allowed_css_keywords.include?(keyword) &&
keyword !~ /^(#[0-9a-f]+|rgb\(\d+%?,\d*%?,?\d*%?\)?|\d{0,2}\.?\d{0,2}(cm|em|ex|in|mm|pc|pt|px|%|,|\))?)$/
!allowed_css_keywords.include?(keyword) &&
keyword !~ /\A(#[0-9a-f]+|rgb\(\d+%?,\d*%?,?\d*%?\)?|\d{0,2}\.?\d{0,2}(cm|em|ex|in|mm|pc|pt|px|%|,|\))?)\z/
end
clean << prop + ': ' + val + ';'
end
@@ -249,6 +249,11 @@ def test_should_sanitize_div_style_expression
assert_equal '', sanitize_css(raw)
end

def test_should_sanitize_across_newlines
raw = %(\nwidth:\nexpression(alert('XSS'));\n)
assert_equal '', sanitize_css(raw)
end

def test_should_sanitize_img_vbscript
assert_sanitized %(<img src='vbscript:msgbox("XSS")' />), '<img />'
end

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