CVE-2026-54513: Fasterxml Jackson-Databind

High severity, CVSS 8.1. EPSS: 1.2% chance of exploitation in the next 30 days.

jackson-databind contains the general-purpose data-binding functionality and tree-model for Jackson Data Processor. From 2.10.0 until 2.18.8, 2.21.4, and 3.1.4, BasicPolymorphicTypeValidator.Builder.allowIfSubTypeIsArray() allowlists any array type based only on clazz.isArray(), without validating the array's component (element) type against the configured allowlist. A PTV built with allowIfSubTypeIsArray() plus an explicit concrete-type allowlist therefore still permits EvilType[] even though EvilType is not allowlisted. When Jackson deserializes the elements and no per-element type IDs are present, it instantiates the component type directly with no further PTV check, bypassing the allowlist. This vulnerability is fixed in 2.18.8, 2.21.4, and 3.1.4.

Affected products

• Fasterxml Jackson-Databind: from 2.10.0, before 2.18.8 (fixed in 2.18.8); from 2.19.0, before 2.21.4 (fixed in 2.21.4); from 3.0.0, before 3.1.4 (fixed in 3.1.4)

Published 2026-06-23. Last modified 2026-09-14.