CVE-2026-90819Network attack vectorHinoki check available

Header injection via unsanitized notification credentials

Published Sep 14, 2026 · Updated Sep 14, 2026

HTTP response splitting in A2A Java SDK 1.2.0 allows remote attackers to inject headers into outbound push-notification requests. BasePushNotificationSender.dispatchNotification builds the Authorization header from token, scheme, and credential values without rejecting embedded CR or LF characters. Exploitation requires a caller able to register a crafted push-notification configuration and can split HTTP framing or inject additional headers at the receiving webhook.

CVSS severityUnavailable
Unscored
EPSS probability0.39%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

HTTP response splitting in A2A Java SDK 1.2.0 allows remote attackers to inject headers into outbound push-notification requests. BasePushNotificationSender.dispatchNotification builds the Authorization header from token, scheme, and credential values without rejecting embedded CR or LF characters. Exploitation requires a caller able to register a crafted push-notification configuration and can split HTTP framing or inject additional headers at the receiving webhook.

The record

CVE
CVE-2026-90819
Published
Sep 14, 2026
Updated
Sep 14, 2026
Vendor
A2A Project
Product
A2A Java SDK
Classifications
CWE-113, T1190
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 14, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 14, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.2.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

A2A Project · A2A Java SDKversion=1.2.0

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-113Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo