According to Lookout Mobile security company, new form of malware is targeting custom roms and it refferes to CyanogenMod.
The malware labeled jSMSHider by Lookout researchers said that it is predominantly targeting Chinese Android users. The application itself communicates with a remote server and can read and send text messages, install additional applications and open webpages. Although the impact of this malware seems to have impact only on a limited amount of phones and they expect to remain this way (isolated).
Cyanogenmod distribution developers already fixed the security hole with its Cyanogenmod 7.0.3 version release. They recommend that all users must upgrade, saying that the latest version doesnt allow apps to be installed with platform keys on user-controlled storage.