As he suspected that some kind of Linux was running on it, he began to see if he could get a root access on it… and succeeded. The original firmware is full of easter eggs , including an always on telnet server on port 11880.

While people managed to access the device serial console a few weeks ago, the plan was to eventually run OpenWrt since it’s based on the popular Atheros AR9331 WiSoC combined with 64MB RAM and 16MB SPI Flash. It would also be one the smallest OpenWrt capable device with dimensions of 30 x 33 mm.

It turns out the card reader uses u-boot, q3k



Q3k OpenWrt port, based on the 15.05 “Chaos Calmer” release:



https://code.hackerspace.pl/emeryth/openwrt_zsun/



Compiled images and image builder:



https://owncloud.hackerspace.pl/index.php/s/7s5c5RDS7Njgwpv was able to create his own openwrt binary image for the 16MB flash and load it on the reader.Q3k OpenWrt port, based on the 15.05 “Chaos Calmer” release:Compiled images and image builder:

The Zsun Wifi card reader is cheap tiny USB to MicroSD card reader with an integrated wifi chip running Linux, In a nutshell, it is a WiFi access point with more flash (16MB) and RAM (64 MB) than most OpenWrt supported routers. Polish hardware hacker q3k from Warsaw Hackerspace, is a recent and proud owner, it allows him to transfer his pictures to any WiFi-enabled device in a matter of seconds.