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vulnerability / NVI-00015181 / Revision 2

CedarJava has type confusion vulnerability

GitHub lists this reviewed advisory for com.cedarpolicy:cedar-java, com.cedarpolicy:cedar-java, com.cedarpolicy:cedar-java. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.

source listedactiveGHSA-93g4-m6xv-cmvrCVE-2026-55772

This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.

01 / Meaning

Why it matters

Published affected context helps an owner decide what evidence to gather. This report has not examined your application.

CVSS

8.8 high

GitHub source severity; exploitability and local consequence require separate evidence.

As of · GitHub Advisory Database

02 / Applicability

The affected context

Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.

com.cedarpolicy:cedar-java

source listed
  • < 2.3.6

### Summary CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. Under certain circumstances, improper input handling could allow type confusion across the Java-Rust FFI boundary. ### Impact **Record-to-Entity type confusion across the Java-Rust FFI boundary** CedarJava sends authorization requests to the Rust cedar-policy evaluator as JSON. The JSON protocol reserves magic single-key object shapes (`__entity` and `__extn`) for entity references and extension values. When serializing a `CedarMap`, there is no validation preventing these reserved keys from being used. If an integrating service builds a `CedarMap` from caller-supplied key/value data (such as request headers, user-defined metadata, or resource tags), an actor who controls those keys could cause the Rust evaluator to interpret a record as an entity reference. This issue requires the integrating service to build a `CedarMap` where the an actor controls the keys, and a policy must reference that value in a when/unless clause. ### Impacted versions: < 4.9 ### Patches Addressed in CedarJava version 2.3.6, 3.4.1, and 4.9 and above. We recommend

GitHub Advisory Database

com.cedarpolicy:cedar-java

source listed
  • >= 3.1.2, < 3.4.1

### Summary CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. Under certain circumstances, improper input handling could allow type confusion across the Java-Rust FFI boundary. ### Impact **Record-to-Entity type confusion across the Java-Rust FFI boundary** CedarJava sends authorization requests to the Rust cedar-policy evaluator as JSON. The JSON protocol reserves magic single-key object shapes (`__entity` and `__extn`) for entity references and extension values. When serializing a `CedarMap`, there is no validation preventing these reserved keys from being used. If an integrating service builds a `CedarMap` from caller-supplied key/value data (such as request headers, user-defined metadata, or resource tags), an actor who controls those keys could cause the Rust evaluator to interpret a record as an entity reference. This issue requires the integrating service to build a `CedarMap` where the an actor controls the keys, and a policy must reference that value in a when/unless clause. ### Impacted versions: < 4.9 ### Patches Addressed in CedarJava version 2.3.6, 3.4.1, and 4.9 and above. We recommend

GitHub Advisory Database

com.cedarpolicy:cedar-java

source listed
  • >= 4.0.0, < 4.9.0

### Summary CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. Under certain circumstances, improper input handling could allow type confusion across the Java-Rust FFI boundary. ### Impact **Record-to-Entity type confusion across the Java-Rust FFI boundary** CedarJava sends authorization requests to the Rust cedar-policy evaluator as JSON. The JSON protocol reserves magic single-key object shapes (`__entity` and `__extn`) for entity references and extension values. When serializing a `CedarMap`, there is no validation preventing these reserved keys from being used. If an integrating service builds a `CedarMap` from caller-supplied key/value data (such as request headers, user-defined metadata, or resource tags), an actor who controls those keys could cause the Rust evaluator to interpret a record as an entity reference. This issue requires the integrating service to build a `CedarMap` where the an actor controls the keys, and a policy must reference that value in a when/unless clause. ### Impacted versions: < 4.9 ### Patches Addressed in CedarJava version 2.3.6, 3.4.1, and 4.9 and above. We recommend

GitHub Advisory Database

03 / Response

What to do next

  1. investigate

    Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.

    Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. NIST National Vulnerability Database

A fixed release is not deployment evidence.

Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.

04 / Limits

What this report cannot establish

  • Customer inventory, deployment, reachability and exploitation have not been inspected.
  • NVD lastModified does not establish freshness of every associated CPE record.
Read the collection and interpretation limits ↗

05 / Provenance

Sources you can inspect

Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.

  1. GHSA-93g4-m6xv-cmvr ↗

    GitHub Advisory Database · vendor advisory

    Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.

  2. CVE-2026-55772 ↗

    NIST National Vulnerability Database · official catalog

    Observed . This product uses data from the NVD API but is not endorsed or certified by the NVD.

Public revision history

Only published revisions appear here. Routine fetches do not create a material-change event.

  1. Revision 2 ·

    Source facts changed; compare the preserved prior revision.

  2. Revision 1 ·

    First indexed by Null; source disclosure date is shown separately.

Read the public revision data ↗

The next step is private

Bring the question into your environment.

The connected workflow is a development preview for inventory, contextual matching, owner decisions and evidence-based verification. No system-specific result is generated by this page.

See the synthetic workflow preview ↗