An issue was discovered in Squid 5.x before 5.0.3. Due to an Incorrect Synchronization, a Denial of Service can occur when processing objects in an SMP cache because of an Ipc::Mem::PageStack::pop ABA problem during access to the memory page/slot management list.
Exploitability
AV:NAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:H6.5/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H