CVE-2026-90820

Received Received - Intake

Missing Authorization in a2a-java 1.2.0 SDK

Publication date: 2026-09-14

Last updated on: 2026-09-14

Assigner: VulDB

Description

A security vulnerability has been detected in a2aproject a2a-java 1.2.0. The impacted element is the function AuthorizationRequestHandlerDecorator.onListTasks of the file server-common/src/main/java/org/a2aproject/sdk/server/requesthandlers/AuthorizationRequestHandlerDecorator.java. Such manipulation leads to missing authorization. The attack can be launched remotely. Upgrading to version 1.3.0 is sufficient to resolve this issue. The name of the patch is e9a1abf9c90c02b16d17293afdc3cc2f555d63a6. The affected component should be upgraded.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-09-14

Last Modified

2026-09-14

Generated

2026-09-15

AI Q&A

2026-09-15

EPSS Evaluated

N/A

NVD

CVE-2026-90820

Affected Vendors & Products

Vendor	Product	Version / Range
a2aproject	a2a-java	1.2.0
a2aproject	a2a-java	to 1.3.0 (inc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-862	The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
CWE-863	The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

Attack-Flow Graph

Executive Summary

This vulnerability is a missing authorization issue in the a2a-java 1.2.0 library. It affects the function AuthorizationRequestHandlerDecorator.onListTasks in the file server-common/src/main/java/org/a2aproject/sdk/server/requesthandlers/AuthorizationRequestHandlerDecorator.java. The flaw allows remote attackers to bypass authorization checks.

Detection Guidance

To detect this vulnerability, check if your system is running a2a-java version 1.2.0. Verify the file server-common/src/main/java/org/a2aproject/sdk/server/requesthandlers/AuthorizationRequestHandlerDecorator.java for the affected function AuthorizationRequestHandlerDecorator.onListTasks. Compare the version against 1.3.0 to confirm if an update is needed.

Impact Analysis

The vulnerability enables unauthorized access to sensitive operations or data due to missing authorization checks. Attackers could remotely exploit this to perform actions they are not permitted to do, potentially leading to data breaches or unauthorized system access.

Compliance Impact

This vulnerability could lead to unauthorized access to personal or sensitive data, violating GDPR and HIPAA requirements for data protection and access control. Compliance may be compromised if unauthorized data exposure occurs.

Mitigation Strategies

Upgrade the a2a-java component to version 1.3.0 or later. The patch e9a1abf9c90c02b16d17293afdc3cc2f555d63a6 resolves the missing authorization issue. Ensure no other instances of version 1.2.0 remain in your environment.

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