An issue was discovered in atftpd in atftp 0.7.1. A remote attacker may send a crafted packet triggering a stack-based buffer overflow due to an insecurely implemented strncpy call. The vulnerability is triggered by sending an error packet of 3 bytes or fewer. There are multiple instances of this vulnerable strncpy pattern within the code base, specifically within tftpdfile.c, tftpfile.c, tftpdmtftp.c, and tftpmtftp.c.

An exploitable denial of service vulnerability exists in the atftpd daemon functionality of atftp 0.7.git20120829-3.1+b1. A specially crafted sequence of RRQ-Multicast requests trigger an assert() call resulting in denial-of-service. An attacker can send a sequence of malicious packets to trigger this vulnerability.

tftpdfile.c in atftp through 0.7.4 has a buffer overflow because buffer-size handling does not properly consider the combination of data, OACK, and other options.

An issue was discovered in atftpd in atftp 0.7.1. It does not lock the threadlistmutex mutex before assigning the current thread data structure. As a result, the daemon is vulnerable to a denial of service attack due to a NULL pointer dereference. If threaddata is NULL when assigned to current, and modified by another thread before a certain tftpdlist.c check, there is a crash when dereferencing current->next.

options.c in atftp before 0.7.5 reads past the end of an array, and consequently discloses server-side /etc/group data to a remote client.