CVE-2026-54513 — jackson-databind: Array subtype allowlist bypass in BasicPolymorphicTypeValidator (allowIfSubTypeIsArray)

Description (CNA)

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 (CNA)

Vendor / product	Versions
FasterXML / jackson-databind	affected >= 2.10.0, < 2.18.8; affected >= 2.19.0, < 2.21.4; affected >= 3.0.0, < 3.1.4

CWE

CWE-184

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

redhat-SADP

A flaw was found in jackson-databind, a library used for processing data. This vulnerability allows an attacker to bypass security controls designed to validate data types. By sending specially crafted input, an attacker can force the system to process untrusted data, which may lead to the execution of malicious code. This could result in a complete compromise of the affected system, impacting its confidentiality, integrity, and availability.