[pmwiki-users] error when editing page

[Patrick R. Michaud]

On Tue, Feb 28, 2006 at 01:05:49PM -0600, matt at flatalbert.com wrote:
> I'm getting an error message when I try to edit *some* of my pages.  
> Here's the error:
> 
> Forbidden
> You don't have permission to access /pmwiki/index.php on this server.
> Additionally, a 404 Not Found error was encountered while trying to  
> use an ErrorDocument to handle the request.
> 
> Some of my pages work fine. Sometimes I can get rid of the error by  
> modifying the text I put in it. I tried to figure out exactly what  
> text was triggering it.
> I found if I put "select from" in my page and try to save it, I'll  
> get that error. I
> 
> Any ideas on what's causing it? It's really annoying.

Your server is probably running apache with mod_security enabled.
The mod_security module looks at the content of incoming requests
(including scanning the contents of POST data) and if it sees anything
suspicious it blocks the request with the "Forbidden" message.

A quick check may be to try saving a page with the string "file(s)"
in it (including the "(s)" part) -- if you get the Forbidden message
then it's likely that mod_security is the culprit.

For sites that are using ISO-8859-1 encoding (which is PmWiki's default),
mod_security will often block pages containing Latin-1 characters
outside of the ASCII set.  This isn't an issue with UTF-8 encoded sites
-- but then again, UTF-8 has its own set of issues to deal with.

There's little that PmWiki can do to work more cleanly with mod_security,
since the post is blocked between the browser and the webserver, before
PmWiki ever receives it.  If you do find that it's mod_security that
is causing the issue, you might see if your administrator can disable
it for the wiki.  

Hope this helps,

Pm