The aeson library is not safe to use to consume untrusted JSON input. A remote user could abuse this flaw to produce a hash collision in the underlying unordered-containers library by sending specially crafted JSON data, resulting in a denial of service.
Severity
CVSS 3.1
6.5 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.9% chance of exploitation in the next 30 days; higher than 58% of CVEs (scores of 2026-10-31)