CVE-2026-54513: Jackson databind Jackson-databind Has An Array Subtype Vulnerability

HIGH
Advisory Identifier: GHSA-rmj7-2vxq-3g9f
Share
CVSS 8.1
CWE-184
Published
Advisory Summary

CVE-2026-54513 is a HIGH (CVSS 8.1) jackson-databind has an array subtype vulnerability (CWE-184: Incomplete List of Disallowed Inputs) affecting Jackson databind libraries in the Maven ecosystem. The issue involves jackson-databind has an array subtype allowlist bypass in basicpolymorphictypevalidator (allowifsubtypeisarray). Remediation is available by upgrading affected packages to version 2.18.8, 2.21.4, 3.1.4.

CVE-2026-54513 at a Glance

CVE Identifier CVE-2026-54513
GHSA Identifier GHSA-rmj7-2vxq-3g9f
Severity HIGH
CVSS v3.1 Base Score 8.1
CWE Classification CWE-184: Incomplete List of Disallowed Inputs
Affected Product Jackson databind
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 8.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2026-54513

To remediate this vulnerability, upgrade all affected Jackson databind dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

com.fasterxml.jackson.core:jackson-databind fixed: 2.18.8 
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.18.8</version>
</dependency>
com.fasterxml.jackson.core:jackson-databind fixed: 2.21.4 
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.21.4</version>
</dependency>
com.fasterxml.jackson.core:jackson-databind fixed: 3.1.4 
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>3.1.4</version>
</dependency>
tools.jackson.core:jackson-databind fixed: 3.1.4 
<dependency>
    <groupId>tools.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>3.1.4</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=com.fasterxml.jackson.core

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-54513, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.fasterxml.jackson.core

Analyze the terminal output to locate any version of Jackson databind in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.18.8), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.fasterxml.jackson.core command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-184: Incomplete List of Disallowed Inputs, where the product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete. In Jackson databind, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

## Summary `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. ## Impact Applications using `BasicPolymorphicTypeValidator` with `allowIfSubTypeIsArray()` as a safeguard get no protection for concrete array component types; an attacker controlling JSON can instantiate non-allowlisted types via an array wrapper, re-opening the gadget-instantiation risk PTV is meant to prevent. ## Affected / Patched (verified via `git tag --contains`) - 2.18 line: `>= 2.10.0, < 2.18.8` -> fixed in **2.18.8** - 2.19-2.21 line: `>= 2.19.0, < 2.21.4` -> fixed in **2.21.4** - 3.x line: `>= 3.0.0, < 3.1.4` -> fixed in **3.1.4** `PolymorphicTypeValidator` was added in 2.10.0 so vulnerability N/A for versions prior to that. ## Severity / CWE Maintainer: significant. Reporter: HIGH. CWE-184 (Incomplete List of Disallowed Inputs); related CWE-502. ## Upstream fix FasterXML/jackson-databind#5981; fix PR #5983 (`24529da`), 2.18 backport PR #5984 (`01d1692`). Released 2026-06-04 in 2.18.8 / 2.21.4 / 3.1.4. ## Credits Omkhar Arasaratnam (@omkhar) - finder.

CVE-2026-54513 Affected Jackson databind Versions

4 component(s)
Fixed Versions:
2.18.82.21.43.1.4
Product / Package Ecosystem Affected Versions Fixed Version
com.fasterxml.jackson.core:jackson-databind
maven/com.fasterxml.jackson.core/jackson-databind
Maven
≥ 2.10.0
< 2.18.8
2.18.8
com.fasterxml.jackson.core:jackson-databind
maven/com.fasterxml.jackson.core/jackson-databind
Maven
≥ 2.19.0
< 2.21.4
2.21.4
com.fasterxml.jackson.core:jackson-databind
maven/com.fasterxml.jackson.core/jackson-databind
Maven
≥ 3.0.0
< 3.1.4
3.1.4
tools.jackson.core:jackson-databind
maven/tools.jackson.core/jackson-databind
Maven
≥ 3.0.0
< 3.1.4
3.1.4

References

GitHub Advisory / Wiki ADVISORY
https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-rmj7-2vxq-3g9f
NVD — CVE-2026-54513 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54513
Jackson databind Source Repository REPOSITORY
https://github.com/FasterXML/jackson-databind/issues/5983
Jackson databind Source Repository REPOSITORY
https://github.com/FasterXML/jackson-databind/issues/5981
Jackson databind Source Repository REPOSITORY
https://github.com/FasterXML/jackson-databind/pull/5984
Security Fix Commit FIX COMMIT
https://github.com/FasterXML/jackson-databind/commit/24529da29fdf46ff94ca38de9ebf31cd188f5e8e
Security Fix Commit FIX COMMIT
https://github.com/FasterXML/jackson-databind/commit/01d1692c8d0ed03e51a0e3c4f8a9e6908e4931e5
access.redhat.com/errata/rhsa-2026:50... WEB
https://access.redhat.com/errata/RHSA-2026:50849
access.redhat.com/errata/rhsa-2026:54... WEB
https://access.redhat.com/errata/RHSA-2026:54435
access.redhat.com/errata/rhsa-2026:54... WEB
https://access.redhat.com/errata/RHSA-2026:54622
access.redhat.com/errata/rhsa-2026:62... WEB
https://access.redhat.com/errata/RHSA-2026:62260
access.redhat.com/errata/rhsa-2026:66... WEB
https://access.redhat.com/errata/RHSA-2026:66488
access.redhat.com/errata/rhsa-2026:66... WEB
https://access.redhat.com/errata/RHSA-2026:66545
Jackson databind Security Information SECURITY
https://access.redhat.com/security/cve/CVE-2026-54513
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=2492010
Jackson databind Source Repository REPOSITORY
https://github.com/FasterXML/jackson-databind
Jackson databind Security Information SECURITY
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54513.json
access.redhat.com/errata/rhsa-2026:36... WEB
https://access.redhat.com/errata/RHSA-2026:36839
access.redhat.com/errata/rhsa-2026:40... WEB
https://access.redhat.com/errata/RHSA-2026:40895
access.redhat.com/errata/rhsa-2026:41... WEB
https://access.redhat.com/errata/RHSA-2026:41951
access.redhat.com/errata/rhsa-2026:43... WEB
https://access.redhat.com/errata/RHSA-2026:43218
access.redhat.com/errata/rhsa-2026:43... WEB
https://access.redhat.com/errata/RHSA-2026:43400
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44061
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44062
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44063
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44064
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44065
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44066
access.redhat.com/errata/rhsa-2026:44... WEB
https://access.redhat.com/errata/RHSA-2026:44271
access.redhat.com/errata/rhsa-2026:48... WEB
https://access.redhat.com/errata/RHSA-2026:48095
access.redhat.com/errata/rhsa-2026:48... WEB
https://access.redhat.com/errata/RHSA-2026:48151
access.redhat.com/errata/rhsa-2026:50... WEB
https://access.redhat.com/errata/RHSA-2026:50846
access.redhat.com/errata/rhsa-2026:50... WEB
https://access.redhat.com/errata/RHSA-2026:50847
access.redhat.com/errata/rhsa-2026:50... WEB
https://access.redhat.com/errata/RHSA-2026:50848

Frequently Asked Questions

What is CVE-2026-54513?
CVE-2026-54513 is a security vulnerability in Jackson databind involving jackson-databind has an array subtype allowlist bypass in BasicPolymorphicTypeValidator (allowIfSubTypeIsArray) under CWE-184: Incomplete List of Disallowed Inputs.
Which Jackson databind versions are affected?
Affected versions include releases prior to 2.18.8, 2.21.4, 3.1.4 across affected packages: com.fasterxml.jackson.core:jackson-databind, tools.jackson.core:jackson-databind.
What version fixes CVE-2026-54513?
Upgrading to 2.18.8, 2.21.4, 3.1.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is jackson-databind affected?
Yes, com.fasterxml.jackson.core:jackson-databind is affected in releases prior to 2.18.8, 2.21.4, 3.1.4. Upgrade your dependency to 2.18.8, 2.21.4, 3.1.4 or later.
What is the CVSS score of CVE-2026-54513?
CVE-2026-54513 has a CVSS v3.1 base score of 8.1 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2026-54513?
CVE-2026-54513 is classified under CWE-184: Incomplete List of Disallowed Inputs (The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete.).
How can I check Maven dependencies for CVE-2026-54513?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.fasterxml.jackson.core'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rmj7-2vxq-3g9f",
  "modified" : "2026-09-11T15:32:24Z",
  "published" : "2026-06-23T21:22:15Z",
  "aliases" : [ "CVE-2026-54513" ],
  "summary" : "jackson-databind has an array subtype allowlist bypass in BasicPolymorphicTypeValidator (allowIfSubTypeIsArray)",
  "details" : "## Summary\n`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.\n\n## Impact\nApplications using `BasicPolymorphicTypeValidator` with `allowIfSubTypeIsArray()` as a safeguard get no protection for concrete array component types; an attacker controlling JSON can instantiate non-allowlisted types via an array wrapper, re-opening the gadget-instantiation risk PTV is meant to prevent.\n\n## Affected / Patched (verified via `git tag --contains`)\n- 2.18 line: `>= 2.10.0, < 2.18.8` -> fixed in **2.18.8**\n- 2.19-2.21 line: `>= 2.19.0, < 2.21.4` -> fixed in **2.21.4**\n- 3.x line: `>= 3.0.0, < 3.1.4` -> fixed in **3.1.4**\n\n`PolymorphicTypeValidator` was added in 2.10.0 so vulnerability N/A for versions prior to that.\n\n## Severity / CWE\nMaintainer: significant. Reporter: HIGH. CWE-184 (Incomplete List of Disallowed Inputs); related CWE-502.\n\n## Upstream fix\nFasterXML/jackson-databind#5981; fix PR #5983 (`24529da`), 2.18 backport PR #5984 (`01d1692`). Released 2026-06-04 in 2.18.8 / 2.21.4 / 3.1.4.\n\n## Credits\nOmkhar Arasaratnam (@omkhar) - finder.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.fasterxml.jackson.core:jackson-databind"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.10.0"
      }, {
        "fixed" : "2.18.8"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.fasterxml.jackson.core:jackson-databind"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.19.0"
      }, {
        "fixed" : "2.21.4"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.fasterxml.jackson.core:jackson-databind"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0"
      }, {
        "fixed" : "3.1.4"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "tools.jackson.core:jackson-databind"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "3.0.0"
      }, {
        "fixed" : "3.1.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/FasterXML/jackson-databind/security/advisories/GHSA-rmj7-2vxq-3g9f"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-54513"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FasterXML/jackson-databind/issues/5983"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FasterXML/jackson-databind/issues/5981"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FasterXML/jackson-databind/pull/5984"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FasterXML/jackson-databind/commit/24529da29fdf46ff94ca38de9ebf31cd188f5e8e"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FasterXML/jackson-databind/commit/01d1692c8d0ed03e51a0e3c4f8a9e6908e4931e5"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:50849"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:54435"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:54622"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:62260"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:66488"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:66545"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/security/cve/CVE-2026-54513"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2492010"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/FasterXML/jackson-databind"
  }, {
    "type" : "WEB",
    "url" : "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-54513.json"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:36839"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:40895"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:41951"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:43218"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:43400"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44061"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44062"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44063"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44064"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44065"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44066"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:44271"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:48095"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:48151"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:50846"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:50847"
  }, {
    "type" : "WEB",
    "url" : "https://access.redhat.com/errata/RHSA-2026:50848"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-184" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-23T21:22:15Z",
    "nvd_published_at" : "2026-06-23T21:17:02Z"
  }
}