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CVE-2026-55772 (GCVE-0-2026-55772)

Vulnerability from cvelistv5 – Published: 2026-07-13 18:44 – Updated: 2026-07-21 19:02
VLAI
Title
CedarJava has a type confusion vulnerability
Summary
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.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-21 19:02 UTC
CWE
  • CWE-843 - Access of Resource Using Incompatible Type ('Type Confusion')
Assigner
References
Impacted products
Vendor Product Version CPE status
cedar-policy cedar-java Affected: < 2.3.6
Affected: >= 3.1.2, < 3.4.1
Affected: >= 4.0.0, < 4.9.0
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  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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