a2aproject a2a-java 1.2.0 Authorization Header Construction BasePushNotificationSender.java BasePushNotificationSender.dispatchNotification response splitting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k2.40-

Summaryinfo

A vulnerability labeled as critical has been found in a2aproject a2a-java 1.2.0. The impacted element is the function BasePushNotificationSender.dispatchNotification of the file server-common/src/main/java/org/a2aproject/sdk/server/tasks/BasePushNotificationSender.java of the component Authorization Header Construction. Such manipulation leads to response splitting. This vulnerability is uniquely identified as CVE-2026-90819. The attack can be launched remotely. No exploit exists. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in a2aproject a2a-java 1.2.0 and classified as critical. Affected by this issue is the function BasePushNotificationSender.dispatchNotification of the file server-common/src/main/java/org/a2aproject/sdk/server/tasks/BasePushNotificationSender.java of the component Authorization Header Construction. The manipulation with an unknown input leads to a response splitting vulnerability. Using CWE to declare the problem leads to CWE-113. The product receives data from an HTTP agent/component (e.g., web server, proxy, browser, etc.), but it does not neutralize or incorrectly neutralizes CR and LF characters before the data is included in outgoing HTTP headers. Impacted is confidentiality, integrity, and availability.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-90819. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit.

Upgrading to version 1.3.0 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 247a655043f145f6f8e3853724b6a543eaa02001 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Response splitting
CWE: CWE-113 / CWE-93 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: a2a-java 1.3.0
Patch: 247a655043f145f6f8e3853724b6a543eaa02001

Timelineinfo

09/13/2026 Advisory disclosed
09/13/2026 +0 days VulDB entry created
09/13/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 1043/1053
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-90819 (🔒)
GCVE (CVE): GCVE-0-2026-90819
GCVE (VulDB): GCVE-100-403322

Entryinfo

Created: 09/13/2026 21:06
Changes: 09/13/2026 21:06 (61)
Complete: 🔍
Submitter: ez-lbz
Cache ID: 216::103

Submitinfo

Accepted

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