Integer underflow in the Lists_MakeMask() function in lists.c in ngIRCd before 0.8.2 allows remote attackers to cause a denial of service (application crash) and possibly execute arbitrary code via a long MODE line that causes an incorrect length calculation, which leads to a buffer overflow.
Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:HI:HA:H9.8/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H