# CVE-2026-117507: a2aproject a2a-java race condition in TaskManager.saveTaskEvent

Source: https://junglewise.ai/threats/cve-2026-117507-a-security-vulnerability-has-been-detected-in-a2aproject-a2a  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-27. Updated: 2026-10-27  
License: CC BY 4.0 with a link back

CVE-2026-117507 · Severity: medium · CVSS 5.4 · Published 2026-10-27

A2A-Java is a Java SDK for the Agent2Agent protocol used to enable AI agents to communicate. A race condition in the TaskManager component can allow remote attackers to cause data inconsistency or task state corruption when multiple concurrent operations manipulate task events. Exploitation requires network access and could lead to data loss or incorrect task execution.

Technologies: [A2aproject A2a-Java](https://junglewise.ai/threats/technologies/a2a-java). Vendors: [A2aproject](https://junglewise.ai/threats/vendors/a2aproject).

## Quick answers

**Is CVE-2026-117507 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-117507 being exploited in the wild.

**How severe is CVE-2026-117507?** Medium severity, with a CVSS score of 5.4, published 27 October 2026.

**Which products and versions are affected?** A2aproject A2a-Java up to 1.2.0.Final.

**Is there a fix for CVE-2026-117507?** Yes: fixed in 1.3.0.Final. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-117507 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-117507?** Check whether you run A2aproject A2a-Java at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in 1.3.0.Final

## Technical details

The vulnerability is a race condition in the TaskManager.saveTaskEvent function that arises from unserialized concurrent task state transitions. An attacker can exploit this via network access to trigger overlapping task state updates, resulting in invalid state machine transitions or lost task state updates. The fix enforces proper state-machine transition validation and serializes task cancel operations.

## Affected products

- a2aproject a2a-java up to 1.2.0.Final

## Timeline

- 2026-10-27: disclosed

## References

- [https://github.com/a2aproject/a2a-java/](https://github.com/a2aproject/a2a-java/)
- [https://github.com/a2aproject/a2a-java/commit/6b8e1e085c35e970ef0048901cd25850e4791ec2](https://github.com/a2aproject/a2a-java/commit/6b8e1e085c35e970ef0048901cd25850e4791ec2)

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