[ 
https://issues.apache.org/jira/browse/MYFACES-4266?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16696446#comment-16696446
 ] 

ASF GitHub Bot commented on MYFACES-4266:
-----------------------------------------

cnsgithub edited a comment on issue #27: MYFACES-4266: Ajax update fails due to 
invalid characters in response XML (DoS)
URL: https://github.com/apache/myfaces/pull/27#issuecomment-441158458
 
 
   > Of course - but this methods uses char and char[]:
   > 
   > ```
   > public void write(int c) throws IOException 
   > public void write(char[] cbuf, int off, int len) throws IOException 
   > ```
   > There is no need to wrap it by a string
   
   Sorry, I don't see any problem here since `xmlEncode` has been overloaded 
three times to fit all `write` variations, i.e. `write(char[],int,in) `is using 
`xmlEncode(char[])`, `write(int) `is using `xmlEncode(char)` and just 
`write(String,off,len) `is using `xmlEncode(String)`.
   
   Edit: @tandraschko Okay, now I see, just added another commit. :wink: 

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


> Ajax update fails due to invalid characters in response XML (DoS)
> -----------------------------------------------------------------
>
>                 Key: MYFACES-4266
>                 URL: https://issues.apache.org/jira/browse/MYFACES-4266
>             Project: MyFaces Core
>          Issue Type: Bug
>    Affects Versions: 2.3.2
>         Environment: jetty 9.4.14.v20181114
> JDK 10
>            Reporter: cnsgithub
>            Priority: Major
>
> I noticed that the {{<f:ajax />}} update fails when the updated form contains 
> unicode characters, which are not allowed in the [XML 1.0 
> spec|https://www.w3.org/TR/REC-xml/#charsets].
> h2. Expected Behaviour
> If the update response contains characters that are not allowed in XML, they 
> should be filtered by MyFaces before writing the response.
> h2. Actual Behaviour
> Some illegal XML characters are not filtered and therefore the browser fails 
> to parse the response.
> h2. Steps to reproduce
> I created a small github project to reproduce this behaviour: 
> [https://github.com/cnsgithub/mojarra-ajax/tree/myfaces] (branch myfaces)
>  To reproduce:
>  - {{git clone [https://github.com/cnsgithub/mojarra-ajax]}}
>  - {{git checkout myfaces}}
>  - run {{mvn clean package jetty:run}}
>  - after the server has started, open [http://localhost:8080/index.xhtml]
>  - Click the button, the error should occur
> The issue also occurs with user supplied inputs:
>  - open [http://localhost:8080/input.xhtml]
>  - Paste the characters from the {{illegal-xml-chars.txt}} file into the 
> input field
>  - Click the button
> This issue should be addressed with high priority since it is security 
> related (might be exploited for Denial of Service).



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

Reply via email to