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Bug 921331 (CVE-2013-1855) - CVE-2013-1855 rubygem-actionpack: css_sanitization: XSS vulnerability in sanitize_css
Summary: CVE-2013-1855 rubygem-actionpack: css_sanitization: XSS vulnerability in sani...
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2013-1855
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 924297 924298 995659 1030775 1165386 1165387
Blocks:
TreeView+ depends on / blocked
 
Reported: 2013-03-14 02:53 UTC by Kurt Seifried
Modified: 2023-05-13 01:45 UTC (History)
22 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed: 2015-01-17 05:33:49 UTC
Embargoed:


Attachments (Terms of Use)
2-3-css_sanitize.patch (deleted)
2013-03-19 20:58 UTC, Kurt Seifried
no flags Details | Diff
3-0-css_sanitize.patch (deleted)
2013-03-19 20:59 UTC, Kurt Seifried
no flags Details | Diff
3-1-css_sanitize.patch (deleted)
2013-03-19 20:59 UTC, Kurt Seifried
no flags Details | Diff
3-2-css_sanitize.patch (deleted)
2013-03-19 20:59 UTC, Kurt Seifried
no flags Details | Diff


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2013:0698 0 normal SHIPPED_LIVE Moderate: rubygem-actionpack and ruby193-rubygem-actionpack security update 2013-04-02 23:45:32 UTC
Red Hat Product Errata RHSA-2014:1863 0 normal SHIPPED_LIVE Important: Subscription Asset Manager 1.4 security update 2014-11-17 22:08:19 UTC

Description Kurt Seifried 2013-03-14 02:53:52 UTC
XSS vulnerability in sanitize_css in Action Pack

There is an XSS vulnerability in the `sanitize_css` method in Action Pack. This vulnerability has been assigned the CVE identifier CVE-2013-1855.

Versions Affected:  All.
Not affected:       None.
Fixed Versions:     3.2.13, 3.1.12

Impact 
------ 
Carefully crafted text can bypass the sanitization provided in the `sanitize_css` method in Action Pack.  Impacted code will look like this:

    sanitize_css(some_user_input)

All users running an affected release should either upgrade or use one of the work arounds immediately. 

Releases 
-------- 
The 3.2.13 and 3.1.12 releases are available at the normal locations. 

Workarounds 
----------- 
To work around this issue, you can apply the following monkey patch:

```
module HTML
  class WhiteListSanitizer
      # Sanitizes a block of css code. Used by #sanitize when it comes across a style attribute
    def sanitize_css(style)
      # disallow urls
      style = style.to_s.gsub(/url\s*\(\s*[^\s)]+?\s*\)\s*/, ' ')

      # gauntlet
      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

      clean = []
      style.scan(/([-\w]+)\s*:\s*([^:;]*)/) do |prop,val|
        if allowed_css_properties.include?(prop.downcase)
          clean <<  prop + ': ' + val + ';'
        elsif shorthand_css_properties.include?(prop.split('-')[0].downcase)
          unless val.split().any? do |keyword|
            !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
        end
      end
      clean.join(' ')
    end
  end
end
```

Patches 
------- 
To aid users who aren't able to upgrade immediately we have provided patches for the two supported release series.  They are in git-am format and consist of a single changeset. 

* 3-2-css_sanitize.patch - Patch for 3.2 series 
* 3-1-css_sanitize.patch - Patch for 3.1 series 
* 3-0-css_sanitize.patch - Patch for 3.0 series 
* 2-3-css_sanitize.patch - Patch for 2.3 series 

Please note that only the 3.1.x and 3.2.x series are supported at present.  Users of earlier unsupported releases are advised to upgrade as soon as possible as we cannot guarantee the continued availability of security fixes for unsupported releases.

Credits 
-------

Thanks to Charlie Somerville for reporting this!

Comment 8 Kurt Seifried 2013-03-16 05:27:22 UTC
Please note that upstream reports that the patches have an issue and will be reissued this weekend most likely so we might need to respin this fix.

Comment 9 Kurt Seifried 2013-03-19 03:23:03 UTC
I replaced the old (bad) patches with the new ones (same names).

Comment 15 Kurt Seifried 2013-03-19 20:58:35 UTC
Created attachment 712960 [details]
2-3-css_sanitize.patch

Comment 16 Kurt Seifried 2013-03-19 20:59:00 UTC
Created attachment 712961 [details]
3-0-css_sanitize.patch

Comment 17 Kurt Seifried 2013-03-19 20:59:24 UTC
Created attachment 712962 [details]
3-1-css_sanitize.patch

Comment 18 Kurt Seifried 2013-03-19 20:59:50 UTC
Created attachment 712963 [details]
3-2-css_sanitize.patch

Comment 20 Vít Ondruch 2013-03-21 13:58:38 UTC
Can I get tracking bug for F1{7,8}? Thank you.

Comment 21 Jan Lieskovsky 2013-03-21 14:13:34 UTC
Created rubygem-actionpack tracking bugs for this issue

Affects: epel-5 [bug 924297]
Affects: fedora-all [bug 924298]

Comment 22 Murray McAllister 2013-03-27 11:27:25 UTC
Acknowledgements:

Red Hat would like to thank Ruby on Rails upstream for reporting this issue. Upstream acknowledges Charlie Somerville as the original reporter.

Comment 23 errata-xmlrpc 2013-04-02 19:47:22 UTC
This issue has been addressed in following products:

  RHEL 6 Version of OpenShift Enterprise

Via RHSA-2013:0698 https://rhn.redhat.com/errata/RHSA-2013-0698.html

Comment 24 Kurt Seifried 2013-07-26 06:17:59 UTC
The Red Hat Security Response Team has rated this issue as having moderate security impact in CloudForms 1.1. This issue is not currently planned to be addressed in future updates.

Comment 28 Martin Prpič 2014-11-14 16:20:10 UTC
IssueDescription:

A cross-site scripting (XSS) flaw was found in Action Pack. A remote attacker could use this flaw to conduct XSS attacks against users of an application using Action Pack.

Comment 29 errata-xmlrpc 2014-11-17 17:08:48 UTC
This issue has been addressed in the following products:

  Red Hat Subscription Asset Manager 1.4

Via RHSA-2014:1863 https://rhn.redhat.com/errata/RHSA-2014-1863.html


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