Untrusted search path vulnerability in Qualcomm qpopper 4.0 through 4.05 allows local users to execute arbitrary code by modifying the PATH environment variable to reference a malicious smbpasswd program.

The pop_msg function in qpopper 4.0.x before 4.0.5fc2 does not null terminate a message buffer after a call to Qvsnprintf, which could allow authenticated users to execute arbitrary code via a buffer overflow in a mdef command with a long macro name.

Qpopper (aka in.qpopper or popper) 4.0.3 and earlier allows remote attackers to cause a denial of service (CPU consumption) via a very large string, which causes an infinite loop.

qpopper 4.01 with PAM based authentication on Red Hat systems generates different error messages when an invalid username is provided instead of a valid name, which allows remote attackers to determine valid usernames on the system.

Buffer overflow in qpopper (aka qpop or popper) 4.0 through 4.0.2 allows remote attackers to gain privileges via a long username.