CVE 2021-41690

DCMTK through 3.6.6 does not handle memory free properly. The malloced memory for storing all file information are recorded in a global variable LST and are not freed properly. Sending specific requests to the dcmqrdb program can incur a memory leak. An attacker can use it to launch a DoS attack.

See the CVE page on Mitre.org for more details.