Cameron Criswell discovered that UltraJSON contained a memory leak that would occur when parsing large integers. An attacker could possibly use this issue to cause UltraJSON to crash, resulting in a denial of service. This issue only affected Ubuntu 24.04 LTS, Ubuntu 25.10, and Ubuntu 26.04 LTS. (CVE-2026-32874) It was discovered that UltraJSON contained integer overflow/underflow issues when calculating how much memory to reserve for indentation in certain instances. An attacker could possibly use this issue to cause UltraJSON to crash, resulting in a denial of service. (CVE-2026-32875)