CVE-2026-55772

CedarJava is an open source Java implementation of the Cedar policy language, used for fine-grained authorization decisions. In versions prior to 2.3.6, 3.4.1 and 4.9.0, under certain circumstances, improper input handling could allow 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. This vulnerability has been fixed in versions 2.3.6, 3.4.1, and 4.9.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/cedar-policy/cedar-java/security/advisories/GHSA-93g4-m6xv-cmvr

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-13 19:17

Updated : 2026-07-21 19:17

NVD link : CVE-2026-55772

Mitre link : CVE-2026-55772

CVE.ORG link : CVE-2026-55772

JSON object : View

Products Affected

No product.

CWE

CWE-843

Access of Resource Using Incompatible Type ('Type Confusion')

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