Answer in brief
CVE-2026-111763 records a Medium severity (CVSS 5.7) vulnerability in A2A Java SDK send client credentials under server-controlled HTTP header name, enabling leakage via redirect. The current sources do not mark it as known exploited. The current feed maps a2aproject/a2a-java (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 5.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps a2aproject/a2a-java (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| a2aproject/a2a-javageneric | <1.3.0.Final | 1.3.0.Final |
Published upstream
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 20, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 20, 2026
A2A Java SDK is the official Java SDK for the Agent2Agent (A2A) Protocol. Prior to 1.3.0.Final, a malicious or compromised remote agent can cause the default JDK-based client to forward a configured API key to a third-party server. When a client application configures credentials through `CredentialService`, `AuthInterceptor.intercept` in `client/transport/spi/src/main/java/org/a2aproject/sdk/client/transport/spi/interceptors/auth/AuthInterceptor.java` uses `APIKeySecurityScheme.name()` from the remote AgentCard directly as the HTTP header name containing the credential, without checking that the declared location is HEADER. JdkA2AHttpClient uses followRedirects(NORMAL), so an agent-controlled cross-origin redirect forwards the custom credential-bearing header even when the standard Authorization header is stripped. The attack requires configured API key credentials for the agent's security scheme and control of the agent's AgentCard and redirect response, but no additional client privileges. This issue is fixed in version 1.3.0.Final.
Quoted source text, attributed separately from HOL analysis.