The unpack implementation in Swoole version 4.0.4 lacks correct size checks in the deserialization process. An attacker can craft a serialized object to exploit this vulnerability and cause a SEGV.
Severity
CVSS 3.0
7.5 high
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
2.3% chance of exploitation in the next 30 days; higher than 83% of CVEs (scores of 2026-10-31)