BIRD Internet Routing Daemon before 1.6.4 allows local users to cause a denial of service (stack consumption and daemon crash) via BGP mask expressions in birdc.
https://gitlab.labs.nic.cz/labs/bird/commit/e8bc64e308586b6502090da2775af84cd760ed0d
https://gitlab.labs.nic.cz/labs/bird/blob/v1.6.4/NEWS#L11