Block Flash content on Squid proxy

Linux, Security
No more flash
No more flash

One of the trending topic I discuss regularly with my company IT department is the need to block Flash content on our navigation proxies.

As a Security people I have no doubt about, Flash must be blocked. Period.

Because I manage some Squid proxy I made this simple and effective configuration in squid.conf  file.

# Block FLASH VIDEO
acl byeflash rep_mime_type -i video/flv video/x-flv ^application/x-shockwave-flash video/f4m video/f4 ^application/.*flash.*
http_reply_access deny byeflash

I made an ACL (byeflash) that match against the mime type of the reply received from Squid proxy (see ACL documentation for more details on rep_mime_type). This is a regexp that look for some specific mime type related to Flash content to block it.

The acl is then applied to http_reply_access configuration directive (see documentation).

Restart squid and say goodbye to Flash!

Published by merlos

Founder and president of Cyber Saiyan - www.cybersaiyan.it - a no profit organization founded to promote social initiatives to spread cyber security and ethical hacking culture; Cyber Saiyan organizes RomHack - www.romhack.io - a cyber security conference held yearly in Rome. I'm heading "Information, systems and network Security" at ENAV, the italian air navigation service provider. Sometimes I write about open source, security and boring stuff on my blog www.scubarda.com

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