Integer overflow in the mod_sftp (aka SFTP) module in ProFTPD 1.3.3d and earlier allows remote attackers to cause a denial of service (memory consumption leading to OOM kill) via a malformed SSH message.

Memory leak in ProFTPd 1.2.0rc2 allows remote attackers to cause a denial of service via a series of USER commands, and possibly SIZE commands if the server has been improperly installed.

An issue was discovered in tls_verify_crl in ProFTPD before 1.3.6. Direct dereference of a NULL pointer (a variable initialized to NULL) leads to a crash when validating the certificate of a client connecting to the server in a TLS client/server mutual-authentication setup.

ProFTPD before 1.3.6b and 1.3.7rc before 1.3.7rc2 allows remote unauthenticated denial-of-service due to incorrect handling of overly long commands because main.c in a child process enters an infinite loop.