Code execution via unchecked array component types
Published Jun 23, 2026 · Updated Aug 26, 2026
Allowlist bypass in FasterXML jackson-databind allows remote attackers to instantiate non-allowlisted types through crafted JSON arrays. BasicPolymorphicTypeValidator.Builder.allowIfSubTypeIsArray() checks only whether the outer class is an array and never validates its component type. Exploitation requires attacker-controlled JSON, the affected array rule, an explicit concrete-type allowlist, and a usable non-allowlisted gadget type.
Summary
What happened
Allowlist bypass in FasterXML jackson-databind allows remote attackers to instantiate non-allowlisted types through crafted JSON arrays. BasicPolymorphicTypeValidator.Builder.allowIfSubTypeIsArray() checks only whether the outer class is an array and never validates its component type. Exploitation requires attacker-controlled JSON, the affected array rule, an explicit concrete-type allowlist, and a usable non-allowlisted gadget type.
The record
- CVE
- CVE-2026-54513
- Published
- Jun 23, 2026
- Updated
- Aug 26, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat JBoss Enterprise Application Platform Expansion Pack
- Classifications
- CWE-184, CWE-502, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 23, 2026CVE publishedPublication date reported by the CVE source.
- Aug 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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