An integer underflow in dpdk versions before 18.11.10 and before 19.11.5 in the `move_desc` function can lead to large amounts of CPU cycles being eaten up in a long running loop. An attacker could cause `move_desc` to get stuck in a 4,294,967,295-count iteration loop. Depending on how `vhost_crypto` is being used this could prevent other VMs or network tasks from being serviced by the busy DPDK lcore for an extended period.
https://www.openwall.com/lists/oss-security/2020/09/28/3
https://usn.ubuntu.com/4550-1/
https://bugzilla.redhat.com/show_bug.cgi?id=1879473
http://www.openwall.com/lists/oss-security/2021/01/04/5
http://www.openwall.com/lists/oss-security/2021/01/04/2
http://www.openwall.com/lists/oss-security/2021/01/04/1
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00006.html
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00004.html