There is a programming flaw in com_media component of joomla content mangement system. Com_media component allows only image(.png, .jpeg, .gif) file to be uploaded to the server. but flaw is that we can upload any html files by changing it name something like example.html.png
Affected Product: Joomla 1.0.13
Proof of Concept:
Below are the steps for POC:
STEP1: first create an html file with any script
STEP2: Login into joomla with administrator
credentials and click on media manager
STEP3: use the image upload utility to upload
crafted png file with name index.html.png
STEP4: joomla will not show any error and file is
STEP5: Then just click on that file and script
code written in that file get executed by
If we change the filename in step2 with example.html then try to upload, joomla will show an error that file type is not supported.
According to me its a serious issue in the joomla image upload alogorithm that does`nt properly validate the format of file uploaded.
If Com_media component is accessible to any user other then above issue can be use to upload any html file remotely. i am not able to com_media component access without administartor credentials.