libcurl would wrongly close the same eventfd file descriptor twice when taking down a connection channel after having completed a threaded name resolve.
Exploitability
AV:NAC:HPR:NUI:NScope
S:UImpact
C:LI:LA:H7/CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H