Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain
-
AccessIdentify endpoint accepting polymorphic JSON
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DeliveryConfirm PTV uses allowIfSubTypeIsArray
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ExploitCraft array payload wrapping denied gadget type
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ExecutionSubmit JSON to deserializer
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PersistPTV approves array, instantiates component without recheck
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ImpactGadget executes attacker-controlled side effect
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A05:2025 - Injection
ASVS 5.0
V2 - Validation and Business Logic Input validation completeness
|
| Exploitation Conditions | Requires the target application to (1) use jackson-databind in an affected version range, (2) construct a BasicPolymorphicTypeValidator that calls allowIfSubTypeIsArray() in combination with an explicit concrete-type allowlist (allowIfSubType), (3) enable polymorphic deserialization via activateDefaultTyping or @JsonTypeInfo against attacker-controlled JSON, and (4) have a usable gadget class available on the classpath for meaningful impact. The bypass specifically only takes effect when no per-element type IDs are present in the JSON, so configurations using JsonTypeInfo.As.PROPERTY with per-element IDs that re-trigger PTV are not exposed. The high attack complexity (CVSS AC:H) reflects these stacked configuration prerequisites. |
| Impact | CVSS 3.1 base score is 8.1 (AV:N/AC:H/PR:N/UI:N/C:H/I:H/A:H) - high impact across CIA but AC:H reflects that exploitation requires the application to (a) use BasicPolymorphicTypeValidator, (b) explicitly call allowIfSubTypeIsArray(), and (c) deserialize attacker-controlled JSON into a polymorphic type without per-element type IDs. No EPSS, KEV, or SSVC data was provided and no public exploit was identified at time of analysis, so this is currently a high-severity supply-chain risk rather than a confirmed mass-exploitation event. The realistic concern is the well-documented gadget-instantiation ecosystem around jackson-databind: any classpath that includes a known gadget (e.g., JNDI-loading classes) becomes RCE-capable once an attacker can re-introduce a denied component type. Note the configuration prerequisite genuinely limits blast radius - applications using PTV without allowIfSubTypeIsArray(), or not using PTV at all, are unaffected by this specific bypass. |
| Exploit ScenarioDerived | An attacker submits JSON to an endpoint that deserializes into a polymorphic field guarded by a PTV configured with allowIfSubTypeIsArray() plus a strict element allowlist; the attacker supplies an array of a non-allowlisted gadget class (e.g., '["java.lang.Object",[{...EvilType payload...}]]'), which the PTV approves at the array level and Jackson then instantiates each component as the denied class via plain bean deserialization. If the classpath contains a known gadget (JNDI lookup, SSRF, file write), this yields the same outcome as historical jackson-databind RCE chains. No public PoC is published yet, but the GitHub issue, fix commits, and diff describe the bypass clearly enough for one to be reproduced. |
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Alert meAnalysisAIv1 – Jun 23, 2026
Allowlist bypass in jackson-databind's BasicPolymorphicTypeValidator (PTV) allows attackers to instantiate non-allowlisted classes by wrapping them in arrays (e.g., EvilType[]), defeating a control intended to block deserialization gadget chains. Affects versions 2.10.0 through 2.18.7, 2.19.0 through 2.21.3, and 3.0.0 through 3.1.3 when applications use allowIfSubTypeIsArray() alongside an explicit concrete-type allowlist. No public exploit identified at time of analysis, but the upstream fix and full root-cause writeup are public on GitHub.
RemediationAI
Vendor-released patches: upgrade to jackson-databind 2.18.8, 2.21.4, or 3.1.4 depending on your branch (released 2026-06-04, see GHSA-rmj7-2vxq-3g9f and PRs #5983 and #5984). Note a behavior change: after upgrading, allowIfSubTypeIsArray() now validates element types, so callers that implicitly relied on 'allow every array' must also allowlist the concrete element types they expect, or array deserialization will start failing - review serialization tests before rolling to production. If immediate patching is not possible, remove the allowIfSubTypeIsArray() call from your PTV configuration and instead explicitly allowlist the concrete element classes you need with allowIfSubType(Class) (trade-off: code change and possible loss of legitimate array support); alternatively avoid Default Typing entirely and use @JsonTypeInfo with a tight type ID resolver, which routes per-element types back through PTV.
Affected VersionsENISA
Affected Packages
Source: OSV (Open Source Vulnerabilities)
Affects your stack
Affects 5 packages in maven, euvd
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
jackson-databind is the FasterXML data-binding layer for the Jackson JSON processor and the de-facto JSON library across the Java ecosystem. PolymorphicTypeValidator (PTV), introduced in 2.10.0, is the safeguard added after the long history of Jackson deserialization-gadget CVEs; BasicPolymorphicTypeValidator.Builder.allowIfSubTypeIsArray() was supposed to permit array container types while still relying on the validator to gate concrete component types. The validator only checked clazz.isArray() and never recursed into the component type, so when Default Typing or @JsonTypeInfo carried no per-element type IDs, Jackson instantiated the component class through normal bean deserialization with no second PTV invocation - the textbook CWE-184 (Incomplete List of Disallowed Inputs), with CWE-502 (Unsafe Deserialization) as the downstream impact class. The fix replaces the always-true array matcher with an _acceptArrayTypes flag that unwraps arrays recursively and validates the innermost element type against the configured matchers.
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Severity by source
AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Network-reachable JSON input with no auth, but AC:H because exploitation requires a specific PTV builder configuration and a usable classpath gadget; full CIA impact via deserialization.
Primary rating from Vendor (github).
CVSS VectorVendor: github
Lifecycle Timeline
1DescriptionCVE.org
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.
Blast Radius
ecosystem impact- 378 maven packages depend on tools.jackson.core:jackson-databind (107 direct, 271 indirect)
Ecosystem-wide dependent count for version 3.0.0.
Executive ViewAI
Jackson-databind versions 2.10.0-2.18.7, 2.19.0-2.21.3, and 3.0.0-3.1.3 contain a critical allowlist bypass in the BasicPolymorphicTypeValidator that permits attackers to instantiate unintended classes through array-wrapped deserialization payloads, enabling arbitrary code execution. All Java applications using affected versions to deserialize untrusted JSON data face direct exposure to advanced gadget chain attacks.
No vendor-released patch identified at time of analysis. Interim mitigations: (1) Disable allowIfSubTypeIsArray() unless mandatory for business logic; (2) Replace polymorphic type deserialization with explicit type mappings for untrusted inputs; (3) Implement pre-deserialization input validation to detect and reject array-wrapped class patterns; (4) Run affected services with minimal privilege and resource limits; (5) Deploy Web Application Firewall rules targeting suspicious polymorphic deserialization payloads; (6) Enable centralized alerting on serialization exceptions (ClassNotFoundException, InvalidTypeIdException) during request processing.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
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Same weakness CWE-184 – Incomplete List of Disallowed Inputs
View allSame technique Authentication Bypass
View allVendor StatusVendor
SUSE
Severity: Important| Product | Status |
|---|---|
| openSUSE Tumbleweed | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Affected |
| openSUSE Leap 16.0 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5 | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Manager Server Module 4.3 | Affected |
| SUSE Enterprise Storage 7 | Affected |
| SUSE Enterprise Storage 7.1 | Affected |
| SUSE Linux Enterprise Desktop 15 SP2 | Affected |
| SUSE Linux Enterprise Desktop 15 SP3 | Affected |
| SUSE Linux Enterprise Desktop 15 SP4 | Affected |
| SUSE Linux Enterprise Desktop 15 SP5 | Affected |
| SUSE Linux Enterprise Desktop 15 SP6 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP2 | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP3 | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Manager Proxy 4.1 | Affected |
| SUSE Manager Proxy 4.2 | Affected |
| SUSE Manager Retail Branch Server 4.1 | Affected |
| SUSE Manager Retail Branch Server 4.2 | Affected |
| SUSE Manager Server 4.1 | Affected |
| SUSE Manager Server 4.2 | Affected |
| openSUSE Leap 15.3 | Affected |
| openSUSE Leap 15.4 | Affected |
| openSUSE Leap 15.5 | Affected |
| openSUSE Leap 15.6 | Affected |
| suse/manager/5.0/x86_64/server suse/manager/5.0/x86_64/server-attestation suse/multi-linux-manager/5.1/x86_64/server suse/multi-linux-manager/5.1/x86_64/server-attestation suse/multi-linux-manager/5.2/x86_64/server suse/multi-linux-manager/5.2/x86_64/server-attestation | Affected |
EUVD-2026-38593
GHSA-rmj7-2vxq-3g9f
NVD
CVE.org
EPSS
Vulnrichment
VulDB
Exploit-DB