DrayTek Vigor 3900 before v1.5.1.5_Beta, DrayTek Vigor 2960 before v1.5.1.5_Beta and DrayTek Vigor 300B before v1.5.1.5_Beta were discovered to contain a command injection vulnerability via the action parameter at cgi-bin/mainfunction.cgi.
A Format String vulnerability exists in DrayTek Vigor 2960 <= 1.5.1.3, DrayTek Vigor 3900 <= 1.5.1.3, and DrayTek Vigor 300B <= 1.5.1.3 in the mainfunction.cgi file via a crafted HTTP message containing malformed QUERY STRING, which could let a remote malicious user execute arbitrary code.
A stack-based buffer overflow on DrayTek Vigor2960, Vigor3900, and Vigor300B devices before 1.5.1.1 allows remote attackers to execute arbitrary code via the formuserphonenumber parameter in an authusersms action to mainfunction.cgi.