CVE-2026-111761: A2A Java SDK has Server-Side Request Forgery (SSRF) in push-notification delivery
a2aproject · a2a-java
Affected: a2aproject a2a-java · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 48% of scored CVEs
DescriptionCVE.org
A2A Java SDK is the official Java SDK for the Agent2Agent (A2A) Protocol. Prior to 1.3.0.Final, BasePushNotificationSender in server-common sends task data to the URL in TaskPushNotificationConfig without destination validation, scheme restrictions, or bounds on redirects. InMemoryPushNotificationConfigStore.setInfo stores the URL verbatim, and onCreateTaskPushNotificationConfig does not validate the destination. In the default deployment with push notifications enabled, an unauthenticated caller can register a destination through an inline SendMessage configuration or CreateTaskPushNotificationConfig for an existing task, causing task status and artifact updates to send requests from the server's network position to loopback, private, link-local cloud-metadata, IPv6 unique-local, unspecified, or multicast destinations where routing permits. JdkA2AHttpClient and VertxA2AHttpClient follow redirects, allowing a webhook redirect to bypass creation-time destination checks and convert a POST into a GET; hostname-only checks also do not prevent DNS rebinding. Direct POST delivery can push attacker-influenced task data into internal services, whereas a redirected POST-to-GET request drops the body. The sender discards the fetched response and does not expose delivery success or failure, so the demonstrated behavior does not provide response read-back. No credentials or user interaction are required. This issue is fixed in version 1.3.0.Final.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- a2aproject · a2a-java< 1.3.0.Final
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Weakness
- Server-Side Request Forgery
- Vendor
- a2aproject
- Published
- October 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-111761 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.
References
- NVD entrynvd.nist.gov
- CVE recordcve.org
- Weakness CWE-918cwe.mitre.org
- github.com/a2aproject/a2a-java/security/advisories/GHSA-q78c-5jjgithub.com
- github.com/a2aproject/a2a-java/pull/1096github.com
- github.com/a2aproject/a2a-java/commit/b855b2ae37e4bf23f73e7746cegithub.com
- github.com/a2aproject/a2a-java/releases/tag/v1.3.0.Finalgithub.com