XF 1.5 JPG security error


Active member
One of my moderators began to experience this problem. I have not had the issue myself and have not changed anything in the system.

"I'm having difficulty attaching a JPG to a post. It shows a progress bar with a percentage of the upload. When it reaches 100%, I get a security error stating that I should go back, and refresh the page to try to upload again. This happened in 3 different browsers.The JPG was able to be attached once the file size was reduced to 2 MB. The JPG was 8 MB when I received the security error. The site's software is supposed to have a 14.6 MB limit."


Active member
Not that I know of. Never heard of it, but that doesn't mean my Linux guy doesn't have it on there...

So far only one person has had this issue, I just remembered that he runs XP. I'm not sure which browser. I have that question out to him right now and I'm waiting for a reply.


XenForo moderator
Staff member
If it's only affecting one member then it's most likely local to them but it's possible they may be triggering something on the server.

Get them to try with a different browser/device to rule that out.

Chris D

XenForo developer
Staff member
It'll be the post_max_size directive in php.ini.

We tend to include the CSRF token at the end of most forms, if the total size of the POST data exceeds the limit, the request is sent to the server without the CSRF token and when we receive POST requests without a valid CSRF token, we return a security error message.

You will simply need to increase the post_max_size value to be more inline with the max_upload_filesize value.