CVE-2013-0256 (published 2013-03-01T05:40Z)

darkfish.js in RDoc 2.3.0 through 3.12 and 4.x before 4.0.0.preview2.1, as used in Ruby, does not properly generate documents, which allows remote attackers to conduct cross-site scripting (XSS) attacks via a crafted URL.

Severity: MEDIUM
CVSS v2 base score: 4.3 (AV:N/AC:M/Au:N/C:N/I:P/A:N)

Weakness information:
cwe_id: CWE-79
cwe_name: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
description: The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
extended_description: 
            Cross-site scripting (XSS) vulnerabilities occur when:
            
               Untrusted data enters a web application, typically from a web request.
               The web application dynamically generates a web page that contains this untrusted data.
               During page generation, the application does not prevent the data from containing content that is executable by a web browser, such as JavaScript, HTML tags, HTML attributes, mouse events, Flash, ActiveX, etc.
               A victim visits the generated web page through a web browser, which contains malicious script that was injected using the untrusted data.
               Since the script comes from a web page that was sent by the web server, the victim's web browser executes the malicious script in the context of the web server's domain.
               This effectively violates the intention of the web browser's same-origin policy, which states that scripts in one domain should not be able to access resources or run code in a different domain.
            
            There are three main kinds of XSS:
            
               
                  Type 1: Reflected XSS (or Non-Persistent) - 
         			The server reads data directly from the HTTP request and reflects it back in the HTTP response. Reflected XSS exploits occur when an attacker causes a victim to supply dangerous content to a vulnerable web application, which is then reflected back to the victim and executed by the web browser. The most common mechanism for delivering malicious content is to include it as a parameter in a URL that is posted publicly or e-mailed directly to the victim. URLs constructed in this manner constitute the core of many phishing schemes, whereby an attacker convinces a victim to visit a URL that refers to a vulnerable site. After the site reflects the attacker's content back to the victim, the content is executed by the victim's browser.
               
                  Type 2: Stored XSS (or Persistent) - 
               The application stores dangerous data in a database, message forum, visitor log, or other trusted data store. At a later time, the dangerous data is subsequently read back into the application and included in dynamic content. From an attacker's perspective, the optimal place to inject malicious content is in an area that is displayed to either many users or particularly interesting users. Interesting users typically have elevated privileges in the application or interact with sensitive data that is valuable to the attacker. If one of these users executes malicious content, the attacker may be able to perform privileged operations on behalf of the user or gain access to sensitive data belonging to the user. For example, the attacker might inject XSS into a log message, which might not be handled properly when an administrator views the logs.
            
               
                  Type 0: DOM-Based XSS - 
               In DOM-based XSS, the client performs the injection of XSS into the page; in the other types, the server performs the injection. DOM-based XSS generally involves server-controlled, trusted script that is sent to the client, such as Javascript that performs sanity checks on a form before the user submits it. If the server-supplied script processes user-supplied data and then injects it back into the web page (such as with dynamic HTML), then DOM-based XSS is possible.
            
            
            Once the malicious script is injected, the attacker can perform a variety of malicious activities. The attacker could transfer private information, such as cookies that may include session information, from the victim's machine to the attacker. The attacker could send malicious requests to a web site on behalf of the victim, which could be especially dangerous to the site if the victim has administrator privileges to manage that site. Phishing attacks could be used to emulate trusted web sites and trick the victim into entering a password, allowing the attacker to compromise the victim's account on that web site. Finally, the script could exploit a vulnerability in the web browser itself possibly taking over the victim's machine, sometimes referred to as "drive-by hacking."
            In many cases, the attack can be launched without the victim even being aware of it. Even with careful users, attackers frequently use a variety of methods to encode the malicious portion of the attack, such as URL encoding or Unicode, so the request looks less suspicious.
         
         

Fix information:
repo_url: https://github.com/rdoc/rdoc
commit_details: repo_url: https://github.com/rdoc/rdoc
author: Eric Hodel
author_date: 2013-02-05 19:57:58-08:00
msg: Fix CVE-2013-0256, an XSS exploit in RDoc

See CVE-2013-0256 for details on the exploit including a patch you can
apply to generated RDoc output.
repository: repo_url: https://github.com/rdoc/rdoc
repo_name: rdoc/rdoc
description: RDoc produces HTML and online documentation for Ruby projects.  RDoc includes the rdoc and ri tools for generating and displaying online documentation.
owner: rdoc
file_changes: filename: CVE-2013-0256.rdoc
change_type: ModificationType.ADD
diff: @@ -0,0 +1,49 @@
+= RDoc 2.3.0 through 3.12 XSS Exploit
+
+RDoc documentation generated by rdoc 2.3.0 through rdoc 3.12 and prereleases up
+to rdoc 4.0.0.preview2.1 are vulnerable to an XSS exploit.  This exploit may
+lead to cookie disclosure to third parties.
+
+The exploit exists in darkfish.js which is copied from the RDoc install
+location to the generated documentation.
+
+RDoc is a static documentation generation tool.  Patching the library itself
+is insufficient to correct this exploit.  Those hosting rdoc documentation will
+need to apply the following patch.  If applied while ignoring whitespace, this
+patch will correct all affected versions:
+
+  diff --git darkfish.js darkfish.js
+  index 4be722f..f26fd45 100644
+  --- darkfish.js
+  +++ darkfish.js
+  @@ -109,13 +109,15 @@ function hookSearch() {
+   function highlightTarget( anchor ) {
+     console.debug( "Highlighting target '%s'.", anchor );
+   
+  -  $("a[name=" + anchor + "]").each( function() {
+  -    if ( !$(this).parent().parent().hasClass('target-section') ) {
+  -      console.debug( "Wrapping the target-section" );
+  -      $('div.method-detail').unwrap( 'div.target-section' );
+  -      $(this).parent().wrap( '<div class="target-section"></div>' );
+  -    } else {
+  -      console.debug( "Already wrapped." );
+  +  $("a[name]").each( function() {
+  +    if ( $(this).attr("name") == anchor ) {
+  +      if ( !$(this).parent().parent().hasClass('target-section') ) {
+  +        console.debug( "Wrapping the target-section" );
+  +        $('div.method-detail').unwrap( 'div.target-section' );
+  +        $(this).parent().wrap( '<div class="target-section"></div>' );
+  +      } else {
+  +        console.debug( "Already wrapped." );
+  +      }
+       }
+     });
+   };
+
+RDoc 3.9.5, 3.12.1 and RDoc 4.0.0.rc.2 and newer are not vulnerable to this
+exploit.
+
+This exploit was discovered by Evgeny Ermakov <corwmh@gmail.com>.
+
+This vulnerability has been assigned the CVE identifier CVE-2013-0256.
+

programming_language: JavaScript
filename: History.rdoc
change_type: ModificationType.MODIFY
diff: @@ -1,4 +1,4 @@
-=== 4.0.0.preview3.1 / ??
+=== 4.0.0.rc.2 / ??
 
 As a preview release, please file bugs for any problems you have with rdoc at
 https://github.com/rdoc/rdoc/issues
@@ -14,6 +14,9 @@ to build HTML documentation when installing gems.)
   * Added current heading and page-top links to HTML headings.
 
 * Bug fixes
+  * Fixed an XSS exploit in darkfish.js.  This could lead to cookie disclosure
+    to third parties.  See CVE-2012-0256.rdoc for full details including a
+    patch you can apply to generated RDoc documentation.
   * Fixed parsing of multibyte files with incomplete characters at byte 1024.
     Ruby bug #6393 by nobu, patch by Nobuyoshi Nakada and Yui NARUSE.
   * Fixed rdoc -E.  Ruby Bug #6392 and (modified) patch by Nobuyoshi Nakada

programming_language: Markdown
filename: Manifest.txt
change_type: ModificationType.MODIFY
diff: @@ -1,5 +1,6 @@
 .autotest
 .document
+CVE-2013-0256.rdoc
 DEVELOPERS.rdoc
 History.rdoc
 LEGAL.rdoc

programming_language: Shell
filename: Rakefile
change_type: ModificationType.MODIFY
diff: @@ -48,6 +48,7 @@ Depending on your version of ruby, you may need to install ruby rdoc/ri data:
   self.testlib = :minitest
   self.extra_rdoc_files += %w[
     DEVELOPERS.rdoc
+    CVE-2013-0256.rdoc
     History.rdoc
     LICENSE.rdoc
     LEGAL.rdoc

programming_language: Ruby
filename: rdoc.rb
change_type: ModificationType.MODIFY
diff: @@ -64,7 +64,7 @@ module RDoc
   ##
   # RDoc version you are using
 
-  VERSION = '4.0.0.preview3.1'
+  VERSION = '4.0.0.rc.2'
 
   ##
   # Method visibilities

programming_language: Ruby
filename: darkfish.js
change_type: ModificationType.MODIFY
diff: @@ -109,13 +109,15 @@ function hookSearch() {
 function highlightTarget( anchor ) {
   console.debug( "Highlighting target '%s'.", anchor );
 
-  $("a[name=" + anchor + "]").each( function() {
-    if ( !$(this).parent().parent().hasClass('target-section') ) {
-      console.debug( "Wrapping the target-section" );
-      $('div.method-detail').unwrap( 'div.target-section' );
-      $(this).parent().wrap( '<div class="target-section"></div>' );
-    } else {
-      console.debug( "Already wrapped." );
+  $("a[name]").each( function() {
+    if ( $(this).attr("name") == anchor ) {
+      if ( !$(this).parent().parent().hasClass('target-section') ) {
+        console.debug( "Wrapping the target-section" );
+        $('div.method-detail').unwrap( 'div.target-section' );
+        $(this).parent().wrap( '<div class="target-section"></div>' );
+      } else {
+        console.debug( "Already wrapped." );
+      }
     }
   });
 };

programming_language: JavaScript